Systems and methods for carbon dioxide reactor control

Abstract

The system optionally comprises a carbon oxide reactor. A method for carbon oxide reactor control optionally comprises selecting an aspect of the carbon oxide reactor based on a desired output composition, operating the carbon oxide reactor under controlled process conditions to produce the desired output composition, and / or varying the process conditions to vary the output composition.

Description

[Technical field]

[0001] [Incorporated by reference] A PCT Request Form is being filed contemporaneously herewith as a part of this application. Each application to which this application claims benefit or priority as identified in the contemporaneously filed PCT Request Form is hereby incorporated by reference in its entirety for all purposes. [Statement of Government Support]

[0002] This invention was made with Government support under Award No. 1738554 awarded by the National Science Foundation, Award Nos. DE-SC0015872, DE-SC0017725, DE-SC0018549, and DE-SC0018549 awarded by the Department of Energy Office of Science, and under Contract Nos. FA864920P0616 and FA8649-19-9-9026 awarded by the United States Air Force. The Government has certain rights in this invention.

[0003] The present disclosure relates generally to the field of carbon oxide reactors, and more particularly to novel and useful systems and methods for reactor control in the field of carbon oxide reactors. [Background technology]

[0004] Exemplary systems and methods for carbon dioxide reactor control include controlling the ratio of carbon monoxide (CO) to other reactor products (e.g., CO:H 2 The focus has been on maximizing aspects of the production of CO and / or other Carbon-Containing Products (CCPs), such as maximizing or adjusting CO2 emission ratios, CO2 concentrations, and / or total CO output or output rates.

[0005] Therefore, there is a need in the field of carbon oxide reactors to create new and useful systems and methods for reactor control. Summary of the Invention

[0006] Aspects of the disclosure relate to a system for producing one or more chemical compounds, the system may feature the following elements: (a) a carbon dioxide capture unit configured to capture carbon dioxide from an impure carbon dioxide source and output carbon dioxide at a concentration higher than a concentration of carbon dioxide in the impure carbon dioxide source; (b) a carbon dioxide reduction electrolyzer having a membrane electrode assembly including one or more ion-conducting polymer layers and a cathode catalyst for facilitating the chemical reduction of the carbon dioxide to carbon-containing reaction products; and (c) a heat transfer unit configured to transfer excess heat generated by the carbon dioxide reduction electrolyzer to the carbon dioxide capture unit to facilitate carbon dioxide capture and / or carbon dioxide release by the carbon dioxide capture unit. The system may be configured to provide carbon dioxide from the carbon dioxide capture unit to the carbon dioxide reduction electrolyzer.

[0007] In certain embodiments, the carbon dioxide reduction electrolyzer is configured to generate humidity during operation, and the system is configured to deliver the humidity generated by the carbon dioxide reduction electrolyzer to the carbon dioxide capture unit, and the carbon dioxide capture unit is configured to release captured carbon dioxide upon exposure to the humidity. In certain embodiments, the carbon dioxide capture unit has a sorbent layer configured to capture carbon dioxide at a first temperature and release carbon dioxide at a second temperature. The second temperature may be higher than the first temperature.

[0008] In certain embodiments, the source of impure carbon dioxide comprises air. In certain embodiments, the system is configured to transport excess carbon dioxide from the carbon dioxide reduction reactor to the carbon dioxide capture unit, where the excess carbon dioxide is purified.

[0009] In certain embodiments, the heat transfer unit comprises a heat exchanger configured to receive the excess heat produced by the carbon dioxide reduction electrolyzer.

[0010] In certain embodiments, the system is configured to transport anode water from an outlet of the carbon dioxide capture unit to the heat transfer unit, In such embodiments, the system may be further configured to recirculate the anode water from the heat transfer unit to the carbon dioxide reduction electrolyzer.

[0011] In certain embodiments, the system is configured to transport a gas stream comprising the carbon-containing reaction product from an outlet of the carbon dioxide capture unit to the heat transfer unit. In such embodiments, the system may be further configured to transport anode water from an outlet of the carbon dioxide capture unit to a second heat transfer unit configured to transfer heat to the carbon dioxide capture unit.

[0012] In certain embodiments, the carbon-containing reaction product includes carbon monoxide, and the system is configured to combine hydrogen with the carbon monoxide to produce a synthesis gas. In some implementations, the system includes a water electrolyzer configured to produce the hydrogen. In some cases, the system additionally includes a Fischer-Tropsch reactor configured to receive the synthesis gas. In certain embodiments, the system includes a second heat transfer unit configured to transfer excess heat generated by the Fischer-Tropsch reactor to the carbon dioxide capture unit to facilitate carbon dioxide capture and / or carbon dioxide release by the carbon dioxide capture unit.

[0013] In certain embodiments, the system includes a methanol synthesis reactor configured to receive the synthesis gas. In such embodiments, the system may include a second heat transfer unit configured to transfer excess heat generated by the methanol synthesis reactor to the carbon dioxide capture unit to facilitate carbon dioxide capture and / or carbon dioxide release by the carbon dioxide capture unit.

[0014] Some aspects of the disclosure relate to methods that may be characterized by the following acts: (a) reducing carbon dioxide to a carbon-containing product in a carbon dioxide reduction electrolyzer comprising a membrane electrode assembly having one or more ion-conducting polymer layers and a cathode catalyst for facilitating the chemical reduction of carbon dioxide to the carbon-containing product; (b) transferring excess heat generated by the carbon dioxide reduction electrolyzer to a carbon dioxide capture unit configured to capture carbon dioxide from an impure carbon dioxide source and output carbon dioxide at a concentration higher than a concentration of carbon dioxide from the impure carbon dioxide source; and (c) transferring the output carbon dioxide to the carbon dioxide reduction electrolyzer.

[0015] In some implementations, the method additionally includes the acts of generating humidity while reducing carbon dioxide in the carbon dioxide reduction electrolytic cell, and delivering the humidity to the carbon dioxide capture unit to facilitate release of captured carbon dioxide upon exposure to the humidity.

[0016] In certain embodiments, the method additionally comprises transporting excess carbon dioxide from the carbon dioxide reduction reactor to the carbon dioxide capture unit, where the excess carbon dioxide is purified. In some implementations, the source of impure carbon dioxide includes air.

[0017] In certain embodiments, transferring the excess heat generated by the carbon dioxide reduction electrolyzer to the carbon dioxide capture unit comprises transferring the excess heat to a heat exchanger. In certain embodiments, the carbon dioxide capture unit comprises a sorbent bed that captures carbon dioxide at a first temperature and releases carbon dioxide at a second temperature. The second temperature may be greater than the first temperature.

[0018] In some implementations, transferring excess heat generated by the carbon dioxide reduction electrolyzer to the carbon dioxide capture unit includes transporting anode water from an outlet of the carbon dioxide capture unit to the carbon dioxide capture unit. Such implementations may include the additional operation of recirculating the anode water from the carbon dioxide capture unit to the carbon dioxide reduction electrolyzer.

[0019] In certain embodiments, transferring excess heat generated by the carbon dioxide reduction electrolyzer to the carbon dioxide capture unit comprises transporting a gas stream including the carbon-containing reaction product from an outlet of the carbon dioxide capture unit to the carbon dioxide capture unit, hi some such embodiments, transferring excess heat generated by the carbon dioxide reduction electrolyzer to the carbon dioxide capture unit further comprises transporting anode water from an outlet of the carbon dioxide capture unit to the carbon dioxide capture unit.

[0020] In certain embodiments, the carbon-containing reaction product includes carbon monoxide. The method may further include combining hydrogen with the carbon monoxide to produce a synthesis gas. Such embodiments may additionally include electrolyzing water to produce the hydrogen. Such embodiments additionally include the synthesis gas in a Fischer-Tropsch reactor. In some cases, the method includes transferring excess heat produced by a Fischer-Tropsch reactor to the carbon dioxide capture unit.

[0021] In some embodiments, the method provides the synthesis gas to a methanol synthesis reactor. Such methods may additionally include transferring excess heat produced by the methanol synthesis reactor to the carbon dioxide capture unit.

[0022] Aspects of the present disclosure relate to a system that may feature the following features: (a) a carbon dioxide reduction electrolyzer having a membrane electrode assembly, the membrane electrode assembly having one or more ion-conducting polymer layers and a cathode catalyst for facilitating the chemical reduction of carbon dioxide to carbon-containing compounds; (b) one or more reactors configured to receive the carbon-containing compounds or derivatives of the carbon-containing compounds produced by the carbon dioxide reduction electrolyzer and produce one or more product chemicals; and (c) a heat accepting unit configured to receive excess heat produced by the carbon dioxide reduction electrolyzer and facilitate the production of the one or more product chemicals.

[0023] In certain embodiments, the heat accepting unit is further configured to provide excess heat to the one or more reactors configured to receive the carbon-containing compound or the derivative of the carbon-containing compound produced by the carbon dioxide reduction electrolyzer and produce the one or more product chemicals.

[0024] In certain embodiments, the heat accepting unit comprises a heat exchanger configured to accept the excess heat generated by the carbon dioxide reduction electrolyzer. In certain embodiments, the heat accepting unit comprises a reboiler configured to accept the excess heat generated by the carbon dioxide reduction electrolyzer.

[0025] In certain embodiments, the one or more reactors configured to receive the carbon-containing compound or the derivative of the carbon-containing compound produced by the carbon dioxide reduction electrolyzer include a Fischer-Tropsch reactor. In such embodiments, the heat-accepting unit may be a reformer configured to react gaseous hydrocarbons with water. In certain embodiments, the Fischer-Tropsch reactor is configured to produce naphtha.

[0026] In certain embodiments, the carbon-containing compound is carbon monoxide and the heat-accepting unit is a CO purification unit. The CO purification unit may utilize an adsorbent.

[0027] Aspects of the disclosure relate to a method that may be characterized by the following operations: (a) reducing carbon dioxide to a carbon-containing product in a carbon dioxide reduction electrolyzer having a membrane electrode assembly, the membrane electrode assembly having one or more ion-conducting polymer layers and a cathode catalyst for facilitating the chemical reduction of carbon dioxide to the carbon-containing product; (b) reacting the carbon-containing product or derivatives of the carbon-containing compound produced by the carbon dioxide reduction electrolyzer in one or more reactions to produce one or more product chemicals; and (c) transferring excess heat produced by the carbon dioxide reduction electrolyzer to the one or more reactions to facilitate the production of the one or more product chemicals. The one or more reactions may be endothermic reactions.

[0028] In certain embodiments, (c) comprises providing the excess heat to a heat exchanger configured to receive the excess heat generated by the carbon dioxide reduction electrolyzer.

[0029] In certain embodiments, the one or more reactions include a Fischer-Tropsch reaction. In such embodiments, operation (c) may comprise providing the excess heat to a reformer that reacts gaseous hydrocarbons with water.

[0030] In some embodiments, the carbon-containing compound is CO and operation (c) comprises providing the excess heat to a CO purification unit. The CO purification unit may utilize an adsorbent.

[0031] Some aspects of the present disclosure relate to a system for producing methanol from carbon dioxide. Such a system may feature the following elements: (a) a carbon dioxide reduction electrolyzer having a membrane electrode assembly, the membrane electrode assembly including one or more ion-conducting polymer layers and a cathode catalyst for facilitating the chemical reduction of carbon dioxide to carbon monoxide; (b) a methanol synthesis reactor configured to produce methanol from the carbon monoxide and hydrogen. The system may be configured to transport the carbon monoxide from the carbon dioxide reduction electrolyzer to the methanol synthesis reactor; and (c) a heat transfer unit configured to transfer excess heat produced by the methanol synthesis reactor to auxiliary components of the system.

[0032] In some embodiments, the system additionally comprises a water electrolyzer configured to produce the hydrogen. Such a system may utilize a second heat transfer unit configured to transfer heat generated by the water electrolyzer to the auxiliary components of the system.

[0033] In certain embodiments, the auxiliary component includes a carbon dioxide capture unit configured to capture carbon dioxide from an impure carbon dioxide source and output carbon dioxide at a concentration greater than a concentration of carbon dioxide in the impure carbon dioxide source. In some such embodiments, the heat transfer unit is configured to receive steam containing the excess heat. Further, the heat transfer unit may be configured to output a hot water stream. And, the system may be further configured to transfer the hot water to the methanol synthesis reactor.

[0034] Some aspects of the present disclosure relate to methods that may be characterized by the following operations: (a) reducing carbon dioxide to a carbon-containing product in a carbon dioxide reduction electrolyzer comprising a membrane electrode assembly having one or more ion-conducting polymer layers and a cathode catalyst for facilitating the chemical reduction of carbon dioxide to the carbon monoxide; (b) transporting the carbon monoxide from the carbon dioxide reduction electrolyzer to a methanol synthesis reactor; (c) reacting the carbon monoxide and hydrogen produced by the carbon dioxide reduction electrolyzer in the methanol synthesis reactor to produce methanol; and (d) transferring excess heat produced by the carbon dioxide reduction electrolyzer and / or the methanol synthesis reactor to an auxiliary component.

[0035] Such methods may include the act of electrolyzing water to produce the hydrogen, and may include transferring heat generated by electrolyzing the water to the auxiliary components of the system.

[0036] In certain embodiments, the auxiliary component comprises a carbon dioxide capture unit configured to capture carbon dioxide from an impure carbon dioxide source and output carbon dioxide at a concentration higher than a concentration of carbon dioxide in the impure carbon dioxide source. Certain embodiments include transferring excess heat produced by the methanol synthesis reactor comprises delivering steam containing the excess heat to the carbon dioxide capture unit. Certain embodiments further comprise converting the steam to hot water. Certain embodiments further comprise transferring the hot water to the methanol synthesis reactor.

[0037] Aspects of the present disclosure relate to a system for producing liquid hydrocarbons from carbon dioxide, which may feature: (a) a carbon dioxide reduction electrolyzer having a membrane electrode assembly, the membrane electrode assembly including one or more ionically conductive polymer layers and a cathode catalyst for facilitating the chemical reduction of carbon dioxide to carbon monoxide; (b) a Fischer-Tropsch reactor configured to produce a liquid hydrocarbon mixture from the carbon monoxide and hydrogen. The system may be configured to transport the carbon monoxide from the carbon dioxide reduction electrolyzer to the Fischer-Tropsch reactor; and (c) a heat transfer unit configured to transfer excess heat generated by the Fischer-Tropsch reactor to auxiliary components of the system.

[0038] In certain embodiments, the auxiliary component comprises a reformer configured to react gaseous hydrocarbons with water, hi certain embodiments, the heat transfer unit is configured to transfer the excess heat to the reformer.

[0039] In some embodiments, the system includes a tail gas combustion unit configured to combust tail gas produced by the Fischer-Tropsch reactor to produce carbon dioxide. Such a system may be configured to transport carbon dioxide from the tail gas combustion unit to the carbon dioxide reduction electrolyzer.

[0040] In certain embodiments, the auxiliary component comprises a carbon dioxide capture unit configured to capture carbon dioxide from an impure carbon dioxide source and output carbon dioxide at a concentration greater than a concentration of carbon dioxide in the impure carbon dioxide source. In certain embodiments, the heat transfer unit is configured to receive steam comprising the excess heat. In certain embodiments, the heat transfer unit is configured to output a hot water stream. In certain embodiments, the system is further configured to transfer the hot water to the Fischer-Tropsch reactor.

[0041] Aspects of the disclosure relate to a method that may be characterized by the following operations: (a) reducing carbon dioxide to a carbon-containing product in a carbon dioxide reduction electrolyzer comprising a membrane electrode assembly having one or more ion-conducting polymer layers and a cathode catalyst for facilitating the chemical reduction of carbon dioxide to the carbon monoxide; (b) transporting the carbon monoxide from the carbon dioxide reduction electrolyzer to a Fischer-Tropsch reactor; (c) reacting the carbon monoxide and hydrogen produced by the carbon dioxide reduction electrolyzer in the Fischer-Tropsch reactor to produce liquid hydrocarbons; and (d) transferring excess heat produced by the carbon dioxide reduction electrolyzer and / or the Fischer-Tropsch reactor to an auxiliary component.

[0042] In certain embodiments, the auxiliary component comprises a reformer configured to react gaseous hydrocarbons with water, hi some such embodiments, the excess heat is generated by the carbon dioxide reduction electrolyzer.

[0043] In some cases, the method includes (i) combusting tail gas produced by the Fischer-Tropsch reactor to produce carbon dioxide, and (ii) transporting carbon dioxide produced by combusting the tail gas to the carbon dioxide reduction electrolyzer.

[0044] In certain embodiments, the auxiliary component includes a carbon dioxide capture unit configured to capture carbon dioxide from an impure carbon dioxide source and output carbon dioxide at a concentration greater than a concentration of carbon dioxide in the impure carbon dioxide source. In some embodiments, transferring excess heat generated by the Fischer-Tropsch reactor includes delivering steam containing the excess heat to the carbon dioxide capture unit. In some embodiments, the method includes converting the steam to hot water. In some embodiments, the method includes transferring the hot water to the Fischer-Tropsch reactor.

[0045] These and other features of the present disclosure will be described in detail below with reference to the associated figures. [Brief description of the drawings]

[0046] [Figure 1] 1 is a flowchart representation of one embodiment of a method.

[0047] [Figure 2A] 1 is a schematic representation of one embodiment of a system. [Figure 2B] 2B is a schematic representation of a variation of the embodiment of FIG. 2A.

[0048] [Figure 2C] 1 is a schematic representation of a first example of an embodiment of a system. [Figure 2D] 1 is a schematic representation of a second example of an embodiment of a system.

[0049] [Figure 3A] 1 is an example of the ideal dependence of reactor power on current density. [Figure 3B] 1 is an example of a non-ideal dependence of reactor power on current density.

[0050] [Figure 4] FIG. 1 shows a gas fermentation system including a carbon oxide reduction electrolyzer upstream from a gas fermentation bioreactor.

[0051] [Diagram 5] FIG. 1 illustrates a system including a carbon dioxide electrolyzer configured to produce synthesis gas.

[0052] [Figure 6A] FIG. 1 illustrates a Fischer-Tropsch system configured to produce liquid hydrocarbons where the carbon source is a carbon oxide feedstock such as those containing carbon dioxide and / or carbon monoxide.

[0053] [Figure 6B] FIG. 1 illustrates a Fischer-Tropsch system configured to produce liquid hydrocarbons where the carbon source is a carbon oxide feedstock, and tail gas from the reforming system is reformed to produce additional carbon monoxide and hydrogen.

[0054] [Figure 7A] FIG. 1 illustrates an air capture CO2 electrolyzer system comprising a direct air CO2 capture subsystem and a CO2 reduction electrolyzer subsystem.

[0055] [Figure 7B] FIG. 1 illustrates an air capture CO2 electrolyzer system with a direct air CO2 capture subsystem on a vehicle or vessel.

[0056] [Figure 8] FIG. 1 presents a general representation of a system for producing polycarbonate polymer using a carbon dioxide reduction electrolytic cell.

[0057] [Figure 9] FIG. 1 illustrates an exemplary formate production system including a carbon dioxide reduction electrolyzer, a formate production reactor, and various downstream formate recovery units.

[0058] [Figure 10A] FIG. 1 illustrates a monoethylene glycol (MEG) production system including a carbon oxide electrolyzer, an ethylene oxide production reactor, and a MEG production reactor.

[0059] [Figure 10B] FIG. 1 illustrates a MEG production system including a carbon dioxide electrolyzer and a MEG production reactor.

[0060] [Figure 11] FIG. 1 is a schematic diagram of a system that may be utilized to produce polyethylene terephthalate.

[0061] [Figure 12] FIG. 1 shows a schematic of a system for producing acetic acid from carbon monoxide and hydrogen produced by a carbon dioxide electrolyser.

[0062] [Figure 13] FIG. 1 illustrates a schematic diagram of a system configured to produce diisocyanates from electrolytically generated carbon monoxide.

[0063] [Figure 14] FIG. 1 is a schematic diagram of a system that may be utilized to produce polyurethane.

[0064] [Figure 15] FIG. 1 illustrates a system including a carbon dioxide electrolyzer configured to produce carbon monoxide and hydrogen for use in producing oxalic acid.

[0065] [Figure 16] FIG. 1 illustrates a system configured to produce oxalic acid from carbon monoxide produced by an electrolyzer.

[0066] [Figure 17A] FIG. 1 illustrates a system including a carbon dioxide electrolyser, a metal formate generation reactor, and an oxalic acid formation reactor.

[0067] [Figure 17B] FIG. 1 illustrates a process and some associated components for producing oxalic acid using carbon monoxide from a carbon dioxide electrolyser.

[0068] [Figure 18] FIG. 1 illustrates a system including a carbon dioxide electrolyzer configured to produce carbon monoxide and hydrogen for use in producing oxalic acid.

[0069] [Figure 19]FIG. 1 illustrates a system for demonstrating a carbon monoxide stream containing carbon dioxide and possibly other components such as hydrogen.

[0070] [Figure 20] FIG. 1 illustrates a hybrid carbon monoxide purification system having a cryogenic pre-treatment subsystem and an adsorbent post-treatment subsystem.

[0071] [Figure 21A] FIG. 1 illustrates a system having an upstream direct air capture (DAC) unit configured to concentrate carbon dioxide from air, and a downstream DAC unit configured to remove unreacted CO2 from the product gas of a carbon dioxide electrolyzer.

[0072] [Figure 21B] FIG. 1 illustrates a system having a DAC unit configured to capture carbon dioxide from air and separate unreacted carbon dioxide from the electrolyzer product gas.

[0073] [Figure 22A] FIG. 1 illustrates a system for coupling a carbon oxide reduction electrolyzer to an electrical grid or other source of electrical energy.

[0074] [Figure 22B] FIG. 1 illustrates a further example of a grid management system utilizing a carbon oxide electrolyser. [Figure 22C] FIG. 1 illustrates a further example of a grid management system utilizing a carbon oxide electrolyser.

[0075] [Figure 23A] FIG. 1 illustrates a system for processing a carbon dioxide electrolyser output to produce a mixture of hydrogen and carbon monoxide by first removing carbon monoxide and then removing hydrogen from a carbon dioxide containing stream.

[0076] [Figure 23B]FIG. 1 illustrates a system for processing carbon dioxide electrolyser output to produce a mixture of hydrogen and carbon monoxide by directly removing carbon dioxide.

[0077] [Figure 23C] FIG. 1 illustrates a system for processing a carbon dioxide electrolyser output to produce a mixture of hydrogen and carbon monoxide by first removing carbon monoxide and then removing hydrogen from a carbon dioxide containing stream.

[0078] [Figure 23D] FIG. 1 illustrates a system for processing carbon dioxide electrolyser output to produce a mixture of hydrogen and carbon monoxide by directly removing carbon dioxide.

[0079] [Figure 24A] FIG. 1 illustrates a first integrated system utilising a carbon dioxide electrolyser and a carbon dioxide capture unit (e.g., DAC) and configured to transfer excess heat from the electrolyser to the carbon dioxide capture unit. [Figure 24B] FIG. 1 illustrates a second integrated system utilising a carbon dioxide electrolyser and a carbon dioxide capture unit (e.g., a DAC) and configured to transfer excess heat from the electrolyser to the carbon dioxide capture unit. [Figure 24C] FIG. 13 illustrates a third integrated system utilising a carbon dioxide electrolyser and a carbon dioxide capture unit (e.g., DAC) configured to transfer excess heat from the electrolyser to the carbon dioxide capture unit. [Figure 24D] FIG. 4 illustrates a fourth integrated system utilising a carbon dioxide electrolyser and a carbon dioxide capture unit (e.g., DAC) and configured to transfer excess heat from the electrolyser to the carbon dioxide capture unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0080] The following description of the preferred embodiments is not intended to limit the disclosure to those embodiments, but rather to enable any person skilled in the art to make and use the disclosure. 1. Overview

[0081] Systems and / or methods for carbon dioxide reactor control may be configured to control aspects of the reactor production, such as aspects related to the amount, concentration, and / or ratio of reactor products. The electrochemical carbon oxide reduction cell, along with associated sensing and / or control systems, may be integrated with any of a variety of other chemical processing systems, such as chemical reactors, chemical separation units, purification units, etc. An integrated system may utilize an electrochemical carbon oxide reduction cell and another chemical processing system located upstream, downstream, or in parallel with the electrochemical carbon oxide reduction cell.

[0082] Examples of carbon oxide reactants include carbon dioxide and carbon monoxide, typically, but not necessarily, in the gas phase. Other examples of carbon oxide reactants include carbonate ions and compounds, and bicarbonate ions and compounds.

[0083] Exemplary systems and methods for carbon dioxide reactor control include controlling the ratio of carbon monoxide (CO) to other reactor products (e.g., CO:H 2 These have focused on maximizing aspects of the production of CO and / or other carbon-containing products (CCPs) (e.g., carbon-containing species (CCS)), such as maximizing CO emission ratios, CO concentrations, and / or total CO output or output rates.

[0084] However, for some applications, simply maximizing aspect values ​​may not be desirable, and arbitrary control of such aspects (e.g., dynamic or selective aspect control to bring values ​​within a range of target aspect values) rather than simple maximization may be beneficial. For example, the CO:H ratio of the reactor product may be increased by 100%. 2It may be desirable to selectively control the ratio (e.g., to obtain the highest CO:H ratio possible for a given system and / or process). 2 The ratio is about 1:3 CO:H 2 Such control allows arbitrary control within the spectrum up to 1:2 CO:H. 2 The reactor output can be more effectively used (e.g., reactor output is fed directly to a subsequent input) for applications such as liquid hydrocarbon production via a gas (e.g., syngas) fermentation process (e.g., bioreactors), and / or a chemical synthesis process (e.g., control of the reactor to produce an output ratio), chemical synthesis processes, and / or gas (e.g., syngas) fermentation processes (e.g., bioreactors). 2. System

[0085] The system may include a carbon dioxide reactor, such as a reactor that produces carbon-containing products (e.g., CO, alkanes, alcohols, etc.) and / or hydrogen from an input (e.g., an input stream, such as a fluid stream) that includes carbon dioxide. Exemplary carbon oxide electrolyzers are shown in Figures 2A-2D. The reactor may be configured to accept a gas phase carbon dioxide input and / or use gas phase carbon dioxide to carry out the reaction (e.g., is a gas phase reactor), but may additionally or alternatively accept liquid phase carbon dioxide, supercritical fluid phase carbon dioxide, solid phase carbon dioxide, and / or any other suitable carbon dioxide input. While the discussion herein focuses on carbon dioxide reactors, in many cases the discussion applies equally to carbon monoxide reactors (e.g., electrochemical carbon monoxide reduction reactors) and carbonate and / or bicarbonate reduction reactors. Thus, unless otherwise specified or clear from the context, reference to a carbon dioxide reactor will be understood to be a reference to a carbon oxide reactor more generally. As shown, the reactor may be an electrolytic cell (e.g., an electrochemical reactor), such as a gas-phase polymer electrolyte membrane electrolytic cell, but may additionally or alternatively include any other suitable reactor.

[0086] The reactor may include one or more: electrodes (e.g., anode, cathode), catalysts (e.g., within and / or adjacent to the cathode and / or anode), gas diffusion layers (e.g., adjacent to the cathode and / or anode), and / or flow fields (e.g., defined within and / or adjacent to the electrodes and / or gas diffusion layers, such as one or more flow channels defined across a gas diffusion layer on the opposite side to the cathode). In some embodiments, the reactor includes a membrane stack or membrane electrode assembly (MEA) having one or more polymer electrolyte membranes (PEM) that provide ionic communication between the anode and cathode of the reactor. In certain embodiments, the reactor comprises a membrane stack comprising: a cathode layer comprising a reduction catalyst and an ion conducting polymer; a PEM membrane (e.g., bipolar membranes, monopolar membranes, etc.; membranes comprising one or more anion conductors such as anion exchange membranes (AEMs), proton and / or cation conductors such as proton exchange membranes, and / or any other suitable ion conducting polymers; membranes comprising one or more buffer layers; etc.); and an anode layer comprising an oxidation catalyst and an ion conducting polymer. The ion conducting polymers in each layer can be the same or different ion conducting polymers.

[0087] In some embodiments, one or more of the catalysts (e.g., reduction catalyst, oxidation catalyst) can include catalytic particles such as nanoparticles (e.g., defining a porous network made up of particles). One or more of the catalysts can additionally or alternatively include one or more polymer electrolytes, optionally mixed with the catalytic nanoparticles (e.g., disposed within the porous network, e.g., filling open areas defined by the porous network). The catalytic nanoparticles can define one or more characteristic sizes (e.g., average size, median size, minimum size, maximum size, size at a particular percentile of the particle size distribution, etc.), and / or the porous network can define a porosity (e.g., percentage of empty space within the network), density, circuitousness (e.g., characteristic path length per layer thickness, area, and / or volume, e.g., paths through empty space or paths along interconnected particles), and / or any other suitable porous network metric.

[0088] In some configurations, the bipolar MEA has the following stacking arrangement: cathode layer / cathode buffer layer (anion conducting layer) / cation conducting layer (which may be a PEM) / anode layer. In some implementations, the bipolar MEA has a cathode layer that contains an anion conducting polymer and / or an anode layer that contains a cation conducting layer. In some implementations, the bipolar MEA has an anode buffer layer between the cation conducting layer and the anode layer, which may contain a cation conducting material.

[0089] In some configurations, a bipolar MEA has the following stacking configuration: cathode layer / cation conducting layer (which may be a PEM) / anion conducting layer / anode layer. In some applications, a bipolar MEA having this configuration is configured in a system for reducing a carbonate and / or bicarbonate source, such as an aqueous solution of carbonate and / or bicarbonate.

[0090] In some configurations, the MEA has the following stacking configuration: cathode layer / anion conducting layer / anode layer. In some implementations, the MEA does not have a cation conducting layer between the cathode and anode layers. In some applications, an MEA containing only anion conducting material between the cathode and anode is configured in a system for reducing a carbon monoxide feedstock.

[0091] In one example ("Reactor Configuration A"), the system includes: a carbon fiber paper gas diffusion layer (e.g., Sigracet 39BC); a catalyst layer including approximately 20% by weight of approximately 4 nm gold particles on Vulcan carbon and an anion conducting polymer (e.g., Fumasep FAA-3); a bipolar PEM; and a flow field, such as a single, double, triple, or quadruple serpentine flow field or an interconnected flow field. In a specific example, the electrodes are approximately 25 cm 2 , but any other suitable area may be defined in addition or alternatively.

[0092] In some embodiments, the reactor is a device according to the present application, filed May 3, 2017, entitled “Reactor with Advanced Architecture for the Electrochemical Reaction of CO 2 No. 15 / 586,182, entitled "Reactor for the Preparation of Fluorinated Hydrocarbons, CO and Other Chemical Compounds," which is incorporated herein by reference in its entirety. However, the reactor may additionally or alternatively include any other suitable elements in any suitable arrangement.

[0093] Additional information regarding optional embodiments and / or elements of the systems and / or methods is provided below in U.S. Patent Application Publication No. 2017 / 0321334, filed May 3, 2017, and U.S. Provisional Patent Application No. 62 / 939,960, filed November 25, 2019, which are incorporated by reference in their entireties herein.

[0094] A carbon oxide reduction reactor may comprise more than one cell or MEA. Multiple cells or MEAs may be arranged in a stack and electrically connected to each other in series and / or parallel. Unless otherwise indicated, all references herein to carbon oxide reduction reactors, carbon oxide electrolyzers, etc. embody single cell electrolyzers and multi-cell stacks of electrolyzers.

[0095] The carbon oxide reduction reactor may obtain carbon oxides from a variety of sources. As mentioned, examples of carbon oxide reactants include carbon dioxide, carbon monoxide, carbonates, and / or bicarbonates. In certain embodiments, the carbonates or bicarbonates are provided in the form of an aqueous solution (e.g., an aqueous solution of potassium bicarbonate) that can be delivered to the cathode of the reduction cell. The carbonates and bicarbonates may be obtained from a variety of sources (e.g., minerals) and / or by a variety of reactions (e.g., reacting carbon dioxide with hydroxides).

[0096] The system may optionally include an upstream source of carbon dioxide input connected to the input of the carbon dioxide reactor of the present disclosure, the upstream source being: a biogas production system; an ethanol fermentation system, such as a corn ethanol production system, a beer production system, a wine production system, etc.; a natural gas processing system; a cement production system; a blast furnace system, e.g., a steel blast furnace system capable of producing blast furnace gas; a coke gas production system; a power plant system, such as an oil power plant system, a natural gas power plant system, a coal power plant system, etc.; an oil refinery system; an ethylene production system; an ammonia production system; a hydrogen production system, such as a water gas shift system; a natural gas processing plant (e.g., Benfield process); an ethylene oxide production system; an aluminum smelting system; a liquefied natural gas (LNG) production system; a solid feedstock gasifier (e.g., municipal solid waste, biomass, or coal feedstock); a reformer (e.g., a steam methane reformer, an autothermal reformer); a system for performing a Boudoir reaction; a direct air capture (direct air capture) system for a carbon dioxide process. capture (DAC); a planetary or satellite atmosphere (e.g., the atmosphere of Mars), a satellite soil (e.g., the soil of a satellite of Earth), and / or any other system capable of producing carbon dioxide. An upstream source of carbon dioxide may be directly connected to the input of the carbon dioxide reactor of the present disclosure (e.g., connected to the reduction catalyst via a cathode flow field and / or a gas diffusion layer, etc., and / or serving as an input), or alternatively, the upstream source may be connected, in any order, to a purification system; a gas compression system; or both a purification system and a gas compression system, which are then connected to the input of the carbon dioxide system of the present disclosure. Multiple purification and / or gas compression systems (e.g., scrubbers, etc.) may be utilized.

[0097] The carbon dioxide, carbon monoxide, or carbonate provided as an input to the carbon oxide reduction reactor may have a wide range of concentrations, depending on the reactor's construction and operating conditions. In certain embodiments, the carbon dioxide provided to the carbon dioxide reduction reactor has a concentration of at least about 20 mole percent, or at least about 40 mole percent, or at least about 75 mole percent, or at least about 90 mole percent. In certain embodiments, the carbon dioxide provided to the carbon dioxide reduction reactor has a concentration of between about 40 mole percent and 60 mole percent.

[0098] The upstream source of water for the electrolytic carbon oxide reduction reactor can come from any of a variety of sources and in a variety of forms, such as purified tap water, purified seawater, a by-product of direct air capture of water, optionally with carbon dioxide capture, combustion processes that may also produce a carbon dioxide feedstock, fuel cell by-products, etc.

[0099] The system may include an input of a downstream system capable of converting a chemical output from the carbon dioxide reactor of the present disclosure, connected to the output of the carbon dioxide reactor of the present disclosure. By way of example, the downstream system of the present disclosure may include one or more of: a bioreactor system; a Fischer-Tropsch system; an anaerobic fermentation system; an aerobic fermentation system; a syngas fermentation system; a ketone and / or polyketone production system; a formate production system; a formate ester production system; a formamide production system; a hydroformylation system; a methanol synthesis system; an ethylene polymerization system; a phosgene production system, an isocyanate production system, a polymer (e.g., polycarbonate, polyethylene terephthalate, or polyurethane) production system, a monoethylene glycol production system, a polyethylene glycol production system, and an oxalic acid production system, and / or any other system capable of converting a chemical output from the carbon oxide reduction reactor. The carbon dioxide reactor output of the present disclosure may be directly connected to a downstream system (e.g., via the cathode flow field and / or gas diffusion layer) and / or the carbon dioxide reactor output may be connected, in any order, to a purification system; a gas compression system; or both a purification system and a gas compression system, which then, optionally, connect to the input of a downstream system. Multiple purification systems and / or gas compression systems may be utilized.

[0100] The downstream system may produce a carbon dioxide output in addition to other product outputs. The system may further include a connection between the carbon dioxide-containing output of the downstream system and the input of the carbon dioxide reactor. The carbon dioxide-containing output of the downstream system may be connected directly to the input of the carbon dioxide reactor, or alternatively, the downstream carbon dioxide-containing output may be connected, in any order, to a purification system; a gas compression system; or both a purification system and a gas compression system, which then connect to the input of the carbon dioxide reactor of the present disclosure. Multiple purification systems and / or gas compression systems may be utilized.

[0101] Carbon dioxide reactors produce a wide range of products (e.g., methane, ethylene, carbon monoxide (CO), molecular hydrogen (H)) that can be used in downstream systems and processes. 2 ), ethanol, formate, formic acid, acetate, acetic acid, propanol, butanol, ethane, methanol) can be produced. Different carbon dioxide reactors (e.g., including different layer stacks, catalysts and / or catalyst layers, PEMs, flow fields, gas diffusion layers, cell compression configurations, and / or any other suitable aspects, etc.) can be used to achieve different reduction products (e.g., product compositions such as HCR); however, different reduction products can additionally or alternatively be achieved by adjusting operating parameters and / or differently. Many possible downstream systems and processes are possible for CO 2 (Examples include methane biorecycling, formic acid or formate biorecycling, acetic acid or acetate biorecycling, the Fischer-Tropsch process, and methanol synthesis.) In many of these cases, CO can be recycled using a carbon dioxide recycle system appropriately sized for the particular application. 2 can be fed back from the downstream system output to the input of the carbon dioxide reactor of the present disclosure, increasing the carbon efficiency of the overall process.

[0102] The system may further include an electrical energy source connected to the carbon dioxide reactor, the electrical energy source including one or more of: a solar power system; a wind power system; a geothermal power system; a fossil fuel power system; or any other system capable of generating electrical energy.

[0103] The system may be utilized to store electrical energy in the form of chemical energy. For example, a power producer may generate excess power during off-peak usage periods. Systems including carbon oxide reduction reactors are able to respond quickly to the need to consume the excess power. They do not need to warm up to operate, and they can be cycled between power-on and power-off states without degradation of the carbon dioxide reactor. The ability to respond quickly to power utilization needs allows the system to work well with intermittent power sources, such as solar and wind power systems.

[0104] One embodiment of the system may include an upstream bioreactor, a carbon dioxide reactor, and an intermittent electrical energy source. If power is available from solar, or wind, or low off-peak demand, or other sources, a power availability detector may be used to start the carbon dioxide reactor. In addition, the system may boost the output of the upstream bioreactor, for example, by increasing the temperature of the upstream bioreactor and increasing the flow of nutrients to the upstream bioreactor. For other upstream carbon dioxide sources, other means may be used as needed to increase the flow of carbon dioxide to the input of the carbon dioxide reactor of the present disclosure.

[0105] Any of the systems disclosed herein may include components (e.g., sensors, systems, etc.) that measure conditions, outputs, and inputs in the systems connected to the carbon dioxide reactor. Such components may include chemical property measurement systems such as gas chromatographs, mass spectrometers, infrared spectrometers, visible spectrometers, and / or ultraviolet spectrometers; temperature detectors; flow measurement sensors; power availability detectors; and / or any other monitoring systems. The monitoring systems may monitor parameters of the input and / or output streams, parameters of components of the input and / or output streams (e.g., impurity concentrations, carbon dioxide concentrations, product concentrations, etc.), and / or any other suitable parameters of the streams.

[0106] Any of the systems disclosed herein may include components for responding to conditions measured in a system connected to a carbon dioxide reactor. Such components may include systems for adjusting flow rate, temperature, power consumption, or other system parameters. The system may include one or more carbon dioxide reactors. However, the system may additionally or alternatively include any other suitable elements in any suitable arrangement. In various embodiments, one or more monitoring or sensing components are used in conjunction with a control system including a controller (e.g., including a processor and memory) having appropriately programmed or constructed logic to determine that one or more operating conditions should be modified and cause such operating conditions to be modified. Feedforward and / or feedback control systems may be utilized. 3. Method

[0107] The method may be implemented using any of the components described above, including an electrochemical carbon oxide reduction reactor, but may additionally or alternatively be implemented using any other suitable system. The method optionally includes operating the reactor under controlled process conditions (e.g., as described in more detail below) to produce a desired output (e.g., CO, H) at a desired ratio (e.g., molecular hydrogen to CCP ratio (HCR) and / or molecular CCP to hydrogen ratio). 2 etc.) and / or modifying process conditions (e.g., as shown in FIG. 1) to change the power and / or power rate.

[0108] Operating the reactor can include: providing one or more inputs (e.g., gases, liquids, solids, etc.), such as carbon dioxide, carbon monoxide, a source of carbon oxides (e.g., waste gas), and / or water; subjecting all or a portion of the inputs to a reaction (e.g., by applying a voltage across the device electrodes), thereby producing products; and / or removing the products from the reactor (e.g., as an output gas stream). Such reactions can include, for example, reducing carbon dioxide and / or water to CO (and / or other CCPs, such as formic acid, methanol, glyoxal, methane, acetic acid, glycolaldehyde, ethylene glycol, acetaldehyde, ethanol, ethylene, hydroxyacetone, acetone, aryl alcohols, propionaldehyde, n-propanol, etc.), and / or H. 2 Operating the reactor may include producing products such as, for example, acetylene, ketone, propylene glycol, etc. However, operating the reactor may additionally or alternatively include producing any other suitable reactions and / or may additionally or alternatively include any other suitable elements performed in any suitable manner.

[0109] The method comprises: 2 Desired CCP:H ratio etc. 2 The method may include controlling the system to achieve a set (e.g., aspects) of desired process conditions, such as process conditions known to result in an actual output and a desired output (e.g., ratio). The method may additionally or alternatively include modifying the process conditions based on (e.g., to reduce or eliminate) a difference between the actual output and the desired output. For example, the method may include imposing an initial set of process conditions; 2determining that the output metric differs from the target output metric (e.g., higher or lower than the target); altering one or more process conditions to reduce the difference in the output metric (e.g., reducing or increasing a process condition value, such as a condition where the output metric tends to increase or decrease with increasing process condition value); and optionally continuing to monitor the output metric and / or alter the process conditions (e.g., implementing closed-loop control of the process conditions based on the output metric).

[0110] The method may optionally include determining a target output metric, which functions to determine which parameters or aspects (e.g., critical parameters for a given application or downstream system) should be targeted. For a given process, one or more target output metrics may be selected. The target output metric may be an output metric associated (e.g., pre-determined, prescribed, etc.) with an application (e.g., an application described above such as Fischer-Tropsch); may be a randomly selected output metric; may be an empirically determined output metric (e.g., through repeated testing and monitoring of downstream application performance); may be an optimized output metric (e.g., based on downstream application operating parameters, reactor operating parameters, etc.); may be a user-specified output metric; and / or may be an output metric determined otherwise.

[0111] The method may optionally include determining a target value for the target output metric, which serves to identify a value (from a range of values) to be targeted. In some variations, the target value may be a maximum or minimum value (e.g., a practically achievable maximum or minimum value, a theoretical maximum or minimum value, etc.). However, the target value may additionally or alternatively not be an extreme value (e.g., it may be an intermediate value or a range of values ​​between the maximum and minimum values). The target value may be a value associated with the application (e.g., pre-determined, pre-associated); may be a randomly selected value; may be an empirically determined value (e.g., through iterative target value selection, monitoring of downstream application performance, and target value adjustment based on application performance); may be an optimized value (e.g., based on downstream application operating parameters, reactor operating parameters, etc.); or may be a value determined otherwise. However, the target value may be any other suitable value and may be determined in any suitable manner.

[0112] Under some conditions, the method may achieve greater than 95% (e.g., up to 100%) carbon dioxide conversion (e.g., fractional CO yield), e.g., a system operating under such conditions may achieve at least a threshold conversion metric. However, the method may additionally or alternatively include achieving greater than 50%, 60%, 70%, 80%, 90%; between 10%-100%, e.g., 10%-40%, 30%-50%, 40%-60%, 50%-70%, 60%-75%, 70%-85%, 80%-95%, 90%-95%, 92%-98%, and / or 95%-100% carbon dioxide conversion; and / or any other suitable carbon dioxide conversion.

[0113] The method optionally includes providing the reactor products (or a subset thereof) to downstream consumers of the products (e.g., as described above, such as those related to applications of the reactor output; as described below, such as in the Examples section). The method may optionally include modifying the reactor products after they are produced (e.g., before feeding the modified products to downstream consumers, etc.). Modifying the reactor products may optionally include purifying the products (e.g., by extracting SO from the reactor output stream). x And / or NO x Modifying the reactor product may additionally or alternatively include mixing additional gases (and / or other substances) into the reactor output stream (and / or input stream), e.g., to achieve a desired output metric. In one variation, the CO:H ratio of the reactor output may be reduced by mixing additional gases (and / or other substances) into the reactor output stream (and / or input stream), e.g., to achieve a desired output metric. 2 If the ratio is different from the desired value, the ratio may be adjusted to divert the reactor output to other gases (e.g., substantially pure CO and / or H 2 CO and H, such as pre-generated and stored output of the reactor, output of a second reactor, output of other systems and / or waste gases; 2 For example, the CO:H mixture in the output stream (and / or in any other part of the reactor) can be adjusted by mixing it with another mixture of CO:H 2 The ratio can be monitored (e.g., continuously during reactor production) and deviations from the desired value can be detected by mixing in other gases (e.g., adding CO and / or CO-enriched mixtures to increase the ratio, adding H to reduce the ratio, etc.). 2 and / or H 2This can be compensated for by adding an enriched mixture (e.g., by modifying the process conditions to correct the reactor output (e.g., as described above with respect to closed loop control). In a second variation, where an external gas supply (e.g., the output and / or waste gases of one or more other systems, such as a steel mill) is fed to a downstream consumer (e.g., a gas fermenter), the reactor product is the CCP:H of the external gas supply. 2 Ratio (e.g., CO:H 2 ratio) of the external gas supply (e.g., CCP:H 2 If the ratio differs from the desired value, it is mixed in the reactor product to achieve the desired value. For example, the process conditions are controlled to adjust the CO:H ratio of the reactor product based on the deviation of the external gas supply from the desired value. 2 The ratio can be altered (e.g., increased in response to a CO-deficient external gas supply, decreased in response to a CO-enriched external gas supply) and / or the amount of reactor product mixed into the external gas supply (e.g., to achieve a desired value) can be controlled. However, the reactor output stream can additionally or alternatively be altered in any other suitable manner or used without alteration.

[0114] In some examples, the method includes determining one or more metrics (e.g., operational metrics) associated with one or more upstream and / or downstream elements of the system (e.g., downstream reactors, upstream inputs, etc.). Such operational metrics may include, for example, reactor conditions such as temperature, pressure, etc.; output metrics of downstream reactors and / or upstream sources such as output amount, composition, purity, etc.; metrics associated with other inputs for the downstream reactors such as input amount, composition, purity, etc.; reactor efficiency metrics; and / or any other suitable metrics. In such examples, the method may include modifying the carbon dioxide reactor operation based on the metric (e.g., to improve and / or maintain operation of the downstream reactor; to improve and / or maintain operation of the carbon dioxide reactor, such as to accommodate changes in the upstream source; to improve and / or maintain a target output metric, such as HCR or reduction product concentration, given a varying carbon dioxide source, etc.); for example, by modifying the HCR of the carbon dioxide reactor output. However, the method may additionally or alternatively include determining any other suitable metrics and / or acting (e.g., based on the metric) in any other suitable manner. 4.Process Conditions

[0115] The process conditions can include, for example, input carbon dioxide flow rate and / or pressure, input gas hydration, current density, voltage (e.g., maintained between about 1.5V and 3V, additionally or alternatively operated at less than about 1.5V, between about 2V-2.5V, between about 2V-4V, above about 4V, and / or any other suitable voltage), and / or temperature. The process conditions can additionally or alternatively include system configurations such as aspects of the gas diffusion layers, aspects of the catalyst, aspects of the flow fields, and / or aspects of the PEM. However, any other suitable process conditions can be controlled or targeted. The process conditions can be uncontrolled (e.g., dictated by an upstream system), controlled to meet target values ​​(e.g., the target values ​​can be determined based on the application receiving the reactor output, instantaneous or expected reactor operating parameters, or otherwise determined), or can be otherwise determined.

[0116] The process conditions may be higher than atmospheric pressure (e.g., about 1 atm (101.325 kPa) to 5 atm (506.625 kPa), about 5 atm (506.625 kPa) to 10 atm (1013.25 kPa), about 10 atm (1013.25 kPa) to 20 atm (2026.5 kPa), about 20 atm (2026.5 kPa) to 50 atm (5066.25 kPa), about 50 atm (5066.25 kPa) to 100 atm (10132.5 kPa), about 100 atm (1 0132.5kPa)~300atm(30397.5kPa), approx. 300atm(30397.5kPa)~1000atm(101325kPa), approx. 1atm(101.325kPa)~10atm(1013.25kPa), approx. 5atm(506.625kPa)~50atm(5066.25kPa), approx. 10atm(1013.25kPa)~100atm(10132.5kPa), approx. 20atm(2026.5kPa)~500atm(50662.5kPa) Pa), and / or greater than about 1000 atm (101325 kPa), about 14 psi (96.52664 kPa) to 50 psi (344.738 kPa), about 50 psi (344.738 kPa) to 150 psi (1034.214 kPa), about 100 psi (689.476 kPa) to 300 psi (2068.428 kPa), about 200 psi (1378.952 kPa) to 500 psi (3447.38 kPa), about 500 psi (3447.38 kPa) to 1000 psi (6894.76 kPa), about 750 psi (5171.07 kPa) to 1500 psi (10342.14 kPa), about 1000 psi (6894.76 kPa) to 3000 psi (20684.28 kPa), about 3000 psi (20684.28 kPa) to 10,000 psi (68947.6 kPa), about 10,000 psi (68947.6 kPa) to 20,000 psi (137895.2 kPa), and / or about 20,000 psi (137895.The process conditions may include pressures (e.g., input gas pressures, reactor pressures, etc.) within and / or above a threshold pressure range, such as about 2 kPa (about 1000 psi) or more, and / or higher than typically achievable in electrolytic cells other than gas-phase electrolyzers, but may additionally or alternatively include pressures substantially equal to 1 atmosphere, pressures less than about 1 atmosphere, and / or any other suitable pressure. The process conditions may include pressures (e.g., input gas pressures, reactor pressures, etc.) within and / or above a threshold temperature range, such as about 25° C.-50° C., about 40° C.-60° C., about 50° C.-100° C., about 50° C.-75° C., about 70° C.-100° C., and / or higher than about 100° C., and / or higher than typically achievable in electrolytic cells other than gas-phase electrolyzers, but may additionally or alternatively include temperatures (e.g., reactor temperatures) substantially equal to room temperature (e.g., about 20° C.-30° C.), temperatures less than room temperature, and / or any other suitable temperature. However, the process conditions may additionally or alternatively include any other suitable process conditions.

[0117] A higher carbon dioxide flow rate leads to increased production of CCPs such as CO (e.g., due to higher availability of carbon dioxide for reduction) and therefore increased production of CCPs:H 2 Correspondingly, a lower carbon dioxide flow rate can result in an increase in the CCP formation and CCP:H ratio. 2 In some embodiments, a higher carbon dioxide flow rate may also result in a decrease in the carbon dioxide conversion efficiency, whereby the output stream (e.g., syngas output) is diluted with unreacted carbon dioxide. For example, the carbon dioxide flow rate (e.g., measured at the reactor inlet) may be less than about 0.1 sccm / cm 2 ~1000sccm / cm 2 (For example, about 0.1sccm / cm 2 ~1sccm / cm 2 , about 1sccm / cm 2 ~10sccm / cm 2 , about 10sccm / cm 2 ~100sccm / cm 2 and / or about 100 sccm / cm 2~1000sccm / cm 2 ) may be maintained at one or more values ​​within the range.

[0118] In a first specific example of control based on input gas flow rate, reactor configuration A with a triple serpentine flow field was used, reactor pressure was substantially maintained at 120 psi (827.3712 kPa), and current density was 500 mA / cm 2 and the reactor temperature is substantially maintained at 30° C. In this specific example, substantially pure carbon dioxide gas is input at various flow rates, from 12 sccm / cm 2 , 20sccm / cm 2 , and 40sccm / cm 2 (e.g., measured at the reactor inlet) of approximately 1:1, 2:1.1, and 4:1 CO:H, respectively. 2 Brings ratio.

[0119] In a second specific example of control based on input gas flow rate, reactor configuration A with a serpentine flow field is used, the reactor pressure is substantially maintained at 130 psi (896.3188 kPa), and the current density is 500 mA / cm 2 In this specific example, the flow rate is substantially maintained at 40 sccm / cm 2 The substantially pure carbon dioxide gas input at a flow rate of approximately 8:2 CO:H 2 ratio, while 12sccm / cm 2 This results in a ratio of approximately 1:1.

[0120] Higher carbon dioxide pressures can increase the CCP fraction yield and / or the CCP:H 2 (Correspondingly, lower carbon dioxide pressure may result in an increase in the CCP fraction yield and / or CCP:H ratio. 2First, increasing the carbon dioxide pressure can result in a higher availability of carbon dioxide for reduction, thereby increasing the total production of CCP. Second, higher pressure at the catalyst can reduce water ingress into the catalyst (e.g., from the cathode), thereby lowering the amount of water available for reduction, which in turn reduces the CCP:H ratio. 2 The ratio may be directly increased and / or the competition for catalytic reaction sites and / or the reaction energy may be reduced (e.g., thereby favoring the reduction of carbon dioxide). 2 In some embodiments where a high ratio is desired, high reactor pressures (e.g., greater than 100 psi (689.476 kPa), up to but below the carbon dioxide phase transition pressure, such as the critical pressure of 1070 psi (7377.3932 kPa), etc.) may be utilized. For example, the reactor pressure can be maintained at one or more values ​​within a range of about 1 psi (6.89476 kPa) to 1100 psi (7584.236 kPa) (e.g., about 1 psi (6.89476 kPa) to 10 psi (68.9476 kPa), about 10 psi (68.9476 kPa) to 100 psi (689.476 kPa), about 100 psi (689.476 kPa) to 300 psi (2068.428 kPa), about 200 psi (1378.952 kPa) to 600 psi (4136.856 kPa), and / or about 500 psi (3447.38 kPa) to 1100 psi (7584.236 kPa)), and / or at any other suitable pressure.

[0121] In a specific example of control based on reactor pressure, reactor configuration A with a single serpentine flow field is used, and substantially pure carbon dioxide gas is pumped at approximately 100 sccm / cm 2 The current density was approximately 150mA / cm 2and the reactor temperature is substantially maintained at about 20° C. In this specific example, the reactor pressure is substantially maintained at various pressures, with reactor pressures of 25 psi (172.369 kPa), 50 psi (344.738 kPa), 75 psi (517.107 kPa), and 100 psi (689.476 kPa) providing CO:H ratios of approximately 3:2, 2.4:1, 3:1, and 5:1, respectively. 2 ratios, and resulting in CO fractional yields of approximately 59%, 69%, 75%, and 84%.

[0122] Increased input gas hydration may result in increased reduction of water (e.g., due to higher availability of water for reduction) and therefore, the CCP:H 2 With a substantially pure carbon dioxide input, only a small amount of water reaches the catalyst (coming almost exclusively from the cathode side of the reactor), resulting in a higher CCP:H ratio. 2 In contrast, when a hydrated input gas is used, a large amount of water from the input gas may reach the catalyst and react. For example, the input gas hydration (e.g., the percentage of water vapor in the input gas) can be maintained at one or more values ​​within a range of 0% (e.g., substantially pure carbon dioxide, substantially unhydrated input gas) to 100% (e.g., 0 percent to 1 percent, 1 percent to 3 percent, 3 percent to 5 percent, 5 percent to 7 percent, 7 percent to 10 percent, 10 percent to 15 percent, 15 percent to 25 percent, 25 percent to 50 percent, 50 percent to 75 percent, and / or 75 percent to 100 percent).

[0123] In a specific example of control based on input gas hydration, reactor configuration A with a single serpentine flow field was used, and the current density was 50 mA / cm 2 , the reactor pressure is substantially maintained at 12 psi (82.73712 kPa), and the reactor temperature is substantially maintained at 20° C. In this specific example, varying hydration amounts of carbon dioxide gas are supplied at 100 sccm / cm2 and the pure carbon dioxide input gas is approximately 3:2 CO:H 2 The input gas at 12.2% hydration yields a ratio of approximately 1:5.67 CO:H 2 The intermediate hydration level is between these two values, resulting in a CO:H ratio. 2 Brings ratio.

[0124] The reactor is a CCP and H 2 In an ideal reactor, at low current densities, no water reduction occurs and all the current goes towards carbon dioxide reduction, resulting in a substantially linear dependence of CO production on current and a substantially linear dependence of H 2 whereas at higher current densities, additional current (e.g., above a threshold current at which substantially all of the carbon dioxide has already been consumed) is used to reduce water, resulting in a large increase in H for the additional current (e.g., as shown in FIG. 3A). 2 This results in a substantially linear dependence of production and substantially constant CO production. In many typical reactors, these idealities are relaxed, but two general regimes are still exhibited: in the low current density regime (e.g., as shown in FIG. 3B), CO production is approximately 100% relative to H 2 increases much faster than the generation and then reaches a plateau in the higher current density regime, while H 2 The production increases more rapidly. The method can be implemented to increase the production of CO and / or H by operating over any or all of a wide range of current densities (e.g., controlling reactor operation in low and / or high current density regimes, etc.). 2 Control the formation of CO:H 2 In some embodiments, the use of gas phase input carbon dioxide can allow for relatively high current densities (whereas reactors using aqueous carbon dioxide can only provide tens of mA / cm 2 For example, the method may be limited to a current density of about 1 mA / cm 2 and 100A / cm 2(e.g., about 1 mA / cm 2 ~75mA / cm 2 , about 50mA / cm 2 ~100mA / cm 2 , about 100mA / cm 2 ~200mA / cm 2 , about 200mA / cm 2 ~500mA / cm 2 , about 500mA / cm 2 ~1000mA / cm 2 , about 50mA / cm 2 ~1000mA / cm 2 , about 0.5mA / cm 2 ~10mA / cm 2 , about 1mA / cm 2 ~2mA / cm 2 , about 2mA / cm 2 ~5mA / cm 2 , about 5mA / cm 2 ~10mA / cm 2 , about 5mA / cm 2 ~100mA / cm 2 , about 10mA / cm 2 ~20mA / cm 2 , about 20mA / cm 2 ~50mA / cm 2 , about 50mA / cm 2 ~100mA / cm 2 etc.; about 50mA / cm 2 , about 65mA / cm 2 , about 80mA / cm 2 , about 90mA / cm 2 , about 100mA / cm 2 , about 110mA / cm 2 , about 120mA / cm 2 , about 130mA / cm 2 , about 140mA / cm 2 , about 150mA / cm 2 , about 200mA / cm 2 , about 300mA / cm 2 , about 500mA / cm 2 , about 700mA / cm 2 , about 1000mA / cm 2 , about 1500mA / cm 2The method may include operating at a current density at, above, or below a threshold such as a threshold value, and / or at any other suitable current density.

[0125] In some embodiments, an increase in reactor temperature may increase the CO:H 2 This can result in a decrease in the ratio of CO:H 2 To control the ratio and / or any other suitable output metric, steps may be included to control the reactor temperature within an operating range, such as a range between a minimum temperature (e.g., the freezing temperature of water, such as 0°C) and a maximum temperature (e.g., about 40°C, about 50°C, about 60°C, about 75°C, etc.; the boiling temperature of water, such as 100°C).

[0126] In a specific example of reactor temperature based control, reactor configuration A with a quadruple serpentine flow field was used, and substantially pure carbon dioxide gas was supplied at 70 sccm / cm 2 The input current is 150mA / cm 2 and the reactor pressure is substantially maintained at 100 psi (689.476 kPa). In this specific example, the reactor temperature is substantially maintained at various temperatures, with reactor temperatures of 26.7° C., 35° C., 38.7° C., and 41.9° C. providing CO:H ratios of approximately 1:0.4, 2:1, 1:1.8, and 1:3, respectively. 2 Brings ratio.

[0127] Additionally or alternatively, the properties of the gas diffusion layer (GDL) may be used to enhance the CCP and / or H 2 For example, the hydrophobicity of the GDL can affect the formation of H 2 The generation of more hydrophilic GDL can be modified by H 2 This favors the formation of CCP:H 2 The more hydrophobic GDL reduces the H 2 inhibits the formation of CCP:H 2(Increase the ratio.) Other GDL properties such as thickness and / or pore size can also be used to modify the reactor output.

[0128] Additionally or alternatively, the properties of the membrane (e.g., polymer electrolyte membrane) can be used to determine the CCP and / or H 2 In the example, an anion exchange membrane that favors CCP formation can be used to achieve high CCP:H 2 The ratio can be achieved, H 2 Low CCP:H using a cation exchange membrane that favors production 2 Ratios can be achieved, and a variety of intermediate ratios can be achieved (e.g., membranes that favor anion transport due to higher ratios, membranes that favor cation transport due to lower ratios) using hybrid membranes (e.g., allowing transport of both anions and cations) that exhibit different anion and cation transport properties (e.g., mobility).

[0129] Additionally or alternatively, the characteristics of the catalyst (e.g., particle size, catalyst species, etc.) can be used to determine the CCP and / or H 2 For example, larger catalyst particles can result in poor carbon dioxide transport, thereby inhibiting CCP production and increasing the CCP:H 2 In addition, or alternatively, the relative number of active sites with a high turnover frequency for hydrogen generation ("hydrogen sites") and active sites with a high turnover frequency for carbon dioxide reduction ("carbon dioxide sites") may depend on the catalyst particle size: larger catalyst particles typically have a higher ratio of hydrogen sites to carbon dioxide sites, while smaller catalyst particles may favor CCP production, thereby increasing the ratio. 2In an example, a substantially pure gold catalyst is used to produce a high CCP:H catalyst, while smaller catalyst particles typically have a lower ratio and favor CO production. Additionally or alternatively, the catalyst type (e.g., catalyst species) can be used to control the reactor output, for example, by utilizing a mixture of one or more catalytic materials, where a first set of catalytic materials (e.g., gold) favors carbon dioxide reduction and a second set of catalytic materials (e.g., platinum) favors water reduction. In an example, a substantially pure gold catalyst is used to produce a high CCP:H catalyst. 2 A low CCP:H ratio can be achieved using a substantially pure platinum catalyst. 2 The ratio can be achieved, and various intermediate ratios can be achieved using gold-platinum mixtures of variable composition (e.g., alloy particles, mixtures of gold and platinum particles, etc.) to achieve various intermediate ratios (e.g., more gold for higher ratios, more platinum for lower ratios). The catalyst can additionally or alternatively include V, Cr, Mn, Fe, Co, Ni, Cu, Sn, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Cd, Hf, Ta, W, Re, Ir, Hg, Al, Si, In, Ga, Tl, Pb, Bi, Sb, Te, Sm, Tb, Ce, Nd, and / or combinations thereof. The catalyst can additionally or alternatively be associated with (e.g., bound to, supported by, incorporated into, adjacent to, in contact with, etc.) one or more support structures (e.g., support particles, support matrices, etc.), which can be conductive support structures such as carbon, boron-doped diamond, and / or fluorine-doped tin oxide. However, the catalyst may additionally or alternatively include any other suitable materials.

[0130] In a specific example of control based on catalyst particle size, a variation of reactor configuration A was used having two catalyst particle sizes, both with a reactor temperature substantially maintained at 30° C., a reactor pressure substantially maintained at 100 psi (689.476 kPa), an interconnected flow field, and a flow rate of 10 sccm / cm of substantially pure carbon dioxide gas. 2 The input current is 500mA / cm 2The first set of catalyst particles has a characteristic size of 4 nm (similar to standard reactor configuration A), resulting in an HCR of 1:1.6 and a voltage of 3.8 V. The second set of catalyst particles has a characteristic size of 20 nm, resulting in an HCR of 1:2.8 and a voltage of 4.2 V.

[0131] Additionally or alternatively, the reactor cell compression properties may be used to reduce the amount of CCP and / or H 2 In a specific example of reactor cell compression based control, reactor configuration A was used with two different gasket thicknesses (greater gasket thickness resulting in greater pressure), both with reactor temperature substantially maintained at 30° C., reactor pressure substantially maintained at 100 psi (689.476 kPa), a triple serpentine flow field, and 40 sccm / cm of substantially pure carbon dioxide gas. 2 The input current is 500mA / cm 2 The first gasket is 0.012 inches (0.3048 mm) thick and provides an HCR of 1:4 and a voltage of 3.6 V. The second gasket is 0.010 inches (0.254 mm) thick and provides an HCR of 1:10.1 and a voltage of 3.8 V.

[0132] Additionally or alternatively, the characteristics of the flow field may be used to determine the CCP and / or H 2 In a first specific example of control based on flow field characteristics, reactor configuration A is used under two different sets of process conditions, both of which have the reactor temperature substantially maintained at 30° C. and the reactor pressure substantially maintained at 120 psi (827.3712 kPa). In the first set of conditions, an interconnected flow field is used, and substantially pure carbon dioxide gas is supplied at 10 sccm / cm. 2 The input current is 160mA / cm 2 The CO:H ratio was essentially maintained at 1.6:1. 2In the second set of conditions, a quadruple serpentine flow field was used, with substantially pure carbon dioxide gas at 40 sccm / cm 2 The input current is 120mA / cm 2 The CO:H ratio was essentially maintained at 18.5:1. 2 Brings ratio.

[0133] In a second specific example of flow field characteristic based control, reactor configuration A was used under two different sets of process conditions, both of which consisted of a reactor temperature substantially maintained at 30° C., a reactor pressure substantially maintained at 100 psi (689.476 kPa), and a flow of substantially pure carbon dioxide gas at 40 sccm / cm 2 The input current is 500mA / cm 2 In the first set of conditions, an interconnected flow field was used, a voltage of 3.6 V was maintained substantially, and a CO:H ratio of 1.6:1 was maintained. 2 In the second set of conditions, a triple serpentine flow field was used, a voltage of 3.8 V was maintained essentially, resulting in a CO:H ratio of 10.1:1. 2 Brings ratio.

[0134] However, any other suitable flow field may additionally or alternatively be utilized to control the reactor output, the process conditions may additionally or alternatively include any other suitable reactor conditions, and the method may additionally or alternatively include controlling the reactor output in any suitable manner. 5. Impurity resistance

[0135] In some embodiments, such as those in which the reactor is operated at high pressure and / or the catalyst is held at a low voltage (e.g., a negative voltage relative to the anode), the system and / or method may provide (e.g., compared to other carbon dioxide reactors) a high tolerance to impurities and / or dilute carbon dioxide input, e.g., poisoning by impurities in the reactor input and / or methane CO, O 2 and / or N 2For example, the method may include determining target process conditions (e.g., reactor configuration such as PEM type, high target reactor pressure, etc.) to achieve tolerance to impurity and / or dilute inputs (e.g., always select such process conditions; select such process conditions in response to current and / or expected conditions of reactor inputs such as impure and / or dilute conditions; etc.). These impurities include SO x And / or NO x The reactor input stream may include species typically present in the reactor input stream (e.g., products of coal combustion and / or natural gas combustion, such as the output from a coal-fired or natural gas-fired power plant), and / or any other impurities, such as ammonia, hydrogen sulfide, and mercury. In one example, the system and / or method may include up to 4% CO, 6% O, 2 , 10% N 2 , 800 ppm NO x and / or 100 ppm SO x It is possible to effectively operate using an input stream that contains CO, O 2 , and N 2 The total amount of impurities is, for example, 10% or less.

[0136] In a specific example of dilute input tolerance, reactor configuration A with a single serpentine flow field was used, with a current density of 160 mA / cm 2 The reactor pressure is substantially maintained at 110 psi (758.4236 kPa), the reactor temperature is substantially maintained at 20° C., and carbon dioxide-containing gas with various dilution levels in methane or nitrogen is fed at 200 sccm / cm 2 In this specific example, the reactor performance has a high tolerance of methane dilution up to at least 50% methane, with methane concentrations of 0%, 25%, and 50% being between 9.5:1 and 8.5:1 CO:H 2ratio, and a CO fractional yield greater than 90%. A more significant reduction in performance is observed using 75% methane, reducing the CO fractional yield to approximately 84%. In this specific example, a similar tolerance to nitrogen dilution is observed, with nitrogen concentrations of 0%, 25%, 50%, and 75% resulting in CO:H ratios between 9:1 and 8:1. 2 ratio, with nitrogen concentrations up to 50% resulting in a CO fractional yield higher than 85% (75% nitrogen concentration resulting in a CO fractional yield of approximately 81%).

[0137] In a specific example of impurity tolerance, reactor configuration A with a single serpentine flow field was used, with a current density of 150 mA / cm 2 The reactor pressure is substantially maintained at 100 psi (689.476 kPa), the reactor temperature is substantially maintained between 20° C. and 25° C., and the carbon dioxide-containing gas having various impurities is fed at 100 sccm / cm 2 In this specific example, reactor output metrics (e.g., CO fractional yield) under various impurity conditions are compared to baseline reactor performance under the same conditions, but using carbon dioxide input with substantially no impurities. In this specific example, reactor performance is compared under conditions of 4% CO concentration or less, 800 ppm NO x SO concentration: 120 ppm or less x It was shown that there was no significant deviation from baseline performance at oxygen concentrations below 6% or 7%.

[0138] However, the systems and / or methods may additionally or alternatively exhibit any suitable tolerance to impure and / or diluted inputs, or may exhibit no such tolerance.

[0139] In certain embodiments, the impurity or impurities pass through the carbon oxide reduction reactor to an output stream where they are (a) separated upstream of another chemical reactor and / or (b) passed to another chemical reactor. In embodiments where the impurities in the output stream are passed to another chemical reactor, the impurities may be used by other reactors in the chemical operations of the process. For example, hydrogen sulfide or other sulfur-containing impurities may be utilized by a microbial species in a downstream bioreactor. 6. System configuration selection

[0140] One or more system configurations may be utilized based on output HCR considerations, such as based on a desired output HCR and / or HCR range (e.g., given a particular set of process conditions and / or range of acceptable process conditions).

[0141] In some embodiments, this involves accepting an input comprising carbon oxides in a first reactor (e.g., an electrolytic cell such as a gas-phase electrolyzer) and electrochemically producing from the input (e.g., under a first set of process conditions) a first reduction product (e.g., comprising molecular hydrogen and / or one or more CCPs other than the carbon oxides input in the first HCR). Designing the first reactor and selecting its operating conditions may include determining a desired HCR and / or HCR range (e.g., based on downstream reactor metrics, market price metrics, efficiency metrics, and / or any other suitable metrics) and selecting a system configuration (e.g., for a second reactor) based on the first HCR and / or desired HCR (e.g., such that the second reactor will or can output a reduction product having an HCR closer to the desired HCR relative to the first HCR, optionally substantially under the first set of process conditions, but additionally or alternatively under any other suitable process conditions). For example, a configuration for the second reactor can be selected such that the second reactor produces a second reduction product from the input under conditions substantially identical to those of the first reactor (e.g., while receiving the input under a first set of process conditions), the second reduction product comprising molecular hydrogen and the same CCS as the first reduction product (e.g., comprising substantially all of the species present in the first reduction product), the second reduction product defining a second HCR that is substantially different from the first HCR, and the second HCR can be closer to the desired HCR than the first HCR. For this example and / or any other embodiment described herein, a substantial difference between the first HCR and the second HCR can include the second HCR: being closer to the desired HCR than the first HCR; differing from the first HCR by at least 1%, 5%, 10%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 0.5%-5%, 2%-10%, 5%-25%, 20%-50%, 40%-80%, and / or 75%-100% (e.g., higher or lower than the first HCR); and / or being otherwise different from the first HCR.

[0142] In some embodiments, selecting a system configuration can include selecting one or more aspects of the PEM, such as to vary the output HCR. Such selection can include selecting a membrane composition (e.g., different polymer species) and / or microstructure, selecting a membrane layer thickness, and / or selecting any other suitable aspect of the PEM. In some examples, such selection includes selecting anion exchange membrane and / or proton exchange membrane thickness (e.g., a bipolar PEM closer to the AEM will tend to generate a lower output HCR than a bipolar PEM closer to the proton exchange membrane). In a first specific example, selecting a thinner AEM (e.g., thinner than a reference AEM thickness, such as the thickness of the AEM of the first reactor, thinner than an optimized AEM thickness substantially corresponding to optimal CCP generation, etc.) can result in a reactor configured to generate a higher output HCR, while selecting a thicker AEM (e.g., thicker than the reference AEM thickness, but optionally not thicker than the optimized AEM thickness) can result in a reactor configured to generate a lower output HCR.

[0143] Selecting a system configuration may additionally or alternatively include selecting one or more aspects of a reactor catalyst (e.g., reduction catalyst, oxidation catalyst), such as to modify the output HCR. In some variations, selecting an aspect of a reactor catalyst may include selecting a catalyst layer thickness (e.g., a thicker reduction catalyst will tend to produce a higher HCR). In one example, selecting a thicker reduction catalyst layer (e.g., thicker than a reference reduction catalyst layer thickness, such as a first reactor reduction catalyst layer thickness, thicker than an optimized reduction catalyst layer thickness substantially corresponding to optimal CCP generation, etc.) may result in a reactor configured to produce a higher output HCR, while selecting a thinner reduction catalyst layer (e.g., thinner than a reference reduction catalyst layer thickness, but optionally not thinner than the optimized reduction catalyst layer thickness) may result in a reactor configured to produce a lower output HCR.

[0144] Selecting aspects of the reactor catalyst may additionally or alternatively include selecting a catalyst porosity (e.g., in embodiments where the catalyst layer includes catalyst particles, such as nanoparticles, that define a porous network) (e.g., a more porous reduced catalyst network will tend to produce a lower HCR). In one example, selecting a less porous reduced catalyst network (e.g., less porous than a reference reduced catalyst, such as the porosity of the first reactor reduced catalyst network, less porous than an optimized reduced catalyst that substantially corresponds to optimal CCP production, etc.) may result in a reactor configured to produce a higher output HCR, while selecting a more porous reduced catalyst (e.g., more porous than the reference reduced catalyst, but optionally not more porous than the optimized reduced catalyst) may result in a reactor configured to produce a lower output HCR.

[0145] Selecting aspects of the reactor catalyst may additionally or alternatively include selecting a catalyst to polymer electrolyte ratio (CPR) (e.g., a higher reduction catalyst CPR will tend to produce a higher HCR), for example, by selecting the degree of polymer electrolyte loading into the porous reduction catalyst network (e.g., in embodiments where the catalyst layer includes catalyst particles, such as nanoparticles, and one or more polymer electrolytes, such as where the catalyst particles define a porous network including a polymer electrolyte and / or are mixed with a medium including the polymer electrolyte). In one example, selecting a higher reduction catalyst CPR (e.g., a CPR higher than a reference reduction catalyst CPR, such as the CPR of the first reactor reduction catalyst network, a CPR higher than an optimized reduction catalyst substantially corresponding to an optimal CCP production, etc.) may result in a reactor configured to produce a higher output HCR, while selecting a lower CPR reduction catalyst (e.g., a CPR lower than a reference reduction catalyst, but optionally not lower than an optimized reduction catalyst CPR) may result in a reactor configured to produce a lower output HCR.

[0146] Selecting the reactor catalyst aspect may additionally or alternatively include selecting a characteristic catalyst particle size (e.g., in embodiments where the catalyst layer includes catalyst particles such as nanoparticles) (e.g., larger particle sizes will tend to produce higher HCR). In one example, selecting a larger reduction catalyst particle size (e.g., larger than the particles of a reference reduction catalyst such as the first reactor reduction catalyst, larger than an optimized reduction catalyst substantially corresponding to optimal CCP production, etc.) may result in a reactor configured to produce a higher output HCR, while selecting a smaller reduction catalyst particle size (e.g., smaller than the particles of the reference reduction catalyst, but not smaller than the particles of the optimized reduction catalyst, for example) may result in a reactor configured to produce a lower output HCR. However, the method may additionally or alternatively include selecting any other suitable reactor catalyst aspect.

[0147] The method may additionally or alternatively include selecting the reactor cell compression (e.g., lower compression will tend to result in a higher HCR, and higher compression will tend to result in a lower HCR), the flow field, and / or any other suitable aspects of the system.

[0148] U.S. Provisional Application No. 62 / 619,996, filed January 22, 2018, U.S. Provisional Application No. 62 / 620,109, filed January 22, 2018, and U.S. Provisional Application No. 62 / 685,771, filed June 15, 2018, are each incorporated by reference in their entirety herein.

[0149] Electrolyzer design and operating conditions can be adjusted for a particular application and to produce a cathode output having a specified composition. In some implementations, one or more general principles may be applied to operate to produce a required output stream composition.

[0150] 1. Limiting the availability of carbon dioxide reactant at the cathode active sites and / or increasing the current density at the cathode. These ranges of operating conditions tend to produce the following results: (a) First, reducing the availability of carbon dioxide reactant and / or increasing the current density results in the conversion of CO to CO. 2 The ratio of CO to CO in the output stream increases (i.e., 2 increases); (b) at some point, if we further reduce the availability of the carbon dioxide reactant and / or increase the current density, the hydrogen ion reduction reaction becomes more prominent (i.e., H 2 Electrolyzers that can operate with relatively low carbon dioxide input / availability can have flow fields or gas diffusion components that limit carbon dioxide from reaching the active sites on the electrolyzer cathode. In certain embodiments, non-interlocking flow field designs and CO 2 Such flow field designs with long paths, such as serpentine paths, between the source and the cathode can be used to reduce the CO:H 2 Interdigitated flow fields force the input gas (carbon oxides) through the gas diffusion layers and then out at different locations on the flow field. Non-interdigitated designs have a long continuous path for the carbon oxide feed gas to enter and exit the cathode. The inlet flow paths are separated from the outlet flow paths. In certain embodiments, a relatively thick gas diffusion electrode provides a high ratio of CO to the cathode active sites. 2 Limiting mass transport and therefore CO:CO 2 and / or H 2 :CO ratio.

[0151] 2. Making hydrogen ions relatively more available at the cathode. By making hydrogen ions relatively more available at the cathode, H 2A cathode product stream having a relatively high ratio of hydrogen to CO may be produced. Electrolyzers configured to provide a relatively hydrogen-rich product may utilize designs that (a) deplete the cathode of the carbon dioxide reactant (as described in 1), (b) allow a relatively high flow rate of hydrogen ions to be transported from the anode (where they are produced) to the cathode, and / or (c) operate at a relatively high cell temperature. Electrolyzers that can operate with a relatively high flow rate of hydrogen ions to the cathode may have an MEA with a cation conducting polymer and / or a mixed ion conducting polymer at the cathode. Alternatively or additionally, in MEAs that include a cathode buffer layer, the layer is designed to be relatively thin and / or have a relatively high hydrogen ion transport number.

[0152] 3. Making hydrogen ions less available at the cathode. By making hydrogen ions less available at the cathode, CO:H 2 A cathode product stream having a relatively high proportion of hydrogen may be produced. Electrolyzers configured to provide a relatively hydrogen-depleted product may (a) provide an excess of carbon dioxide reactant to the cathode for a given current density, (b) include an MEA design that prevents hydrogen ions from reaching the cathode, and / or (c) utilize a design that operates at a relatively low cell temperature. high CO 2 Reduction Products vs. CO 2 Ratio Operating Parameter Regime

[0153] In certain embodiments, the electrolytic cell has a ratio of at least about 1:1, or at least about 1:2, or at least about 1:3 CO:CO 2 The system is configured to produce, and during operation does produce, an output stream having a CO molar ratio of at least about 25 mol %, or at least about 33 mol %, or at least about 50 mol %. The high CO output stream may alternatively be characterized as having a CO concentration of at least about 25 mol %, or at least about 33 mol %, or at least about 50 mol %.

[0154] In certain embodiments, this high carbon monoxide output concentration is obtained by operating the carbon dioxide electrolyzer in a manner that produces any one or any combination of the following operating conditions: a current density at the cathode of at least about 300 mA / cm; up to about 4, or up to about 2.5, or up to about 1.5 CO (as described elsewhere herein) 2 stoichiometric flow rate Temperatures up to about 80°C or up to about 65°C, Pressure range: approximately 75 psig (517.107 kPaG) to 400 psig (2757.904 kPaG) an anode water composition of about 0.1 mM to 50 mM bicarbonate; and Anode water pH of at least about 1.

[0155] In certain embodiments, the electrolyser achieves high CO:CO as defined herein by using a carbon dioxide electrolyser having any one or any combination of the following characteristics: 2 The molar ratios or concentrations may be constructed to favor: A relatively small nanoparticle cathode catalyst (e.g., having, on average, a maximum dimension of about 0.1 nm to 15 nm); Gold as a cathode catalyst material; Cathode catalyst layer thickness of about 5um~20um, a cathode gas diffusion layer (GDL) having a microporous layer (MPL); a cathode GDL having PTFE present at about 1 wt.% to 20 wt.%, or about 1 wt.% to 10 wt.%, or about 1 wt.% to 5 wt.%; A GDL having a thickness of at least about 200 um a bipolar MEA having an anion exchange cathode buffer layer having a thickness of at least about 5 um; and Cathode flow field with parallel and / or serpentine flow paths. High reduction products (H2+CO) to CO2 ratio operating parameter regime

[0156] In certain embodiments, the electrolytic cell has a ratio of (H 2 +CO):CO 2 It is configured to produce, and during operation actually produces, an output stream having a molar ratio.

[0157] In certain embodiments, this high reduction product output concentration is obtained by operating the carbon dioxide electrolyzer in a manner that produces any one or any combination of the following operating conditions: a current density of at least about 300 mA / cm; Up to about 4, or up to about 2.5, or up to about 1.5 CO 2 stoichiometric flow rate, Maximum temperature of about 125°C, Maximum pressure of approximately 800 psi (5515.808 kPa), an anode water composition of 0 mM to about 500 mM bicarbonate; and Anode water pH of approximately 0-15.

[0158] In certain embodiments, the electrolyzer achieves high (CO+H) conversion as defined herein by using a carbon dioxide electrolyzer having any one or any combination of the following characteristics: 2 ):CO 2 The molar ratios or concentrations may be constructed to favor: a nanoparticle cathode catalyst (e.g., having, on average, a maximum dimension of about 0.1 nm to 1000 nm); Transition metals as cathode catalyst materials, Cathode catalyst layer thickness of about 0.1um~100um, a cathode gas diffusion layer with or without a microporous layer (MPL); GDL with about 0wt% to 70wt% PTFE, A GDL having a thickness of about 10um to 1000um, and A bipolar MEA with an anion exchange cathode buffer layer that is approximately 0um to 100um thick. Hydrogen-rich product stream operating parameter regime

[0159] In certain embodiments, the carbon dioxide electrolyser contains H in a molar ratio of at least about 1:1. 2 :CO.

[0160] In certain embodiments, such hydrogen-enriched output concentration is obtained by operating the carbon dioxide electrolyzer in a manner that produces any one or any combination of the following operating conditions: a current density of at least about 300 mA / cm; CO to the cathode up to approx. 2 mass transfer stoichiometric flow rate, a temperature of at least about 65° C. or at least about 80° C.; Pressure range: approx. 75 psig (517.107 kPaG) to 500 psig (3447.38 kPaG) an anode water composition of pure water or at least about 50 mM bicarbonate; and Anode water pH of approximately 1 maximum.

[0161] In certain embodiments, the electrolyser may be constructed to favor hydrogen enriched molar ratios or concentrations as defined herein by using a carbon dioxide electrolyser having any one or any combination of the following characteristics: Relatively large nanoparticle cathode catalysts (e.g., having, on average, a maximum dimension of at least about 80 nm) Silver, palladium, or zinc as a cathode catalyst material; A cathode catalyst layer thickness of up to about 5 um or at least about 25 um; a cathode gas diffusion layer without a microporous layer (MPL); a cathode GDL having no PTFE or at least about 20 wt. % PTFE; a cathode GDL having a thickness that is at most about 200 um or at least about 500 um; and A bipolar MEA with an anion exchange cathode buffer layer with a thickness that is about 0um to 5um. Highly reduced product vs. hydrogen product stream operating parameter regimes

[0162] In certain embodiments, the carbon dioxide electrolyser contains at least about a 2:1 molar ratio of CO:H 2 The device is configured to generate, and in operation actually generates, an output stream having

[0163] In certain embodiments, such product-enriched output concentrations are obtained by operating the carbon dioxide electrolyzer in a manner that produces any one or any combination of the following operating conditions: a current density at the cathode of at least about 300 mA / cm; At least about 1.5, or at least about 2.5, or at least about 4 CO to the cathode 2 mass transfer stoichiometric flow rate, Maximum temperature of about 80°C, Pressures in the range of approximately 75 psig (517.107 kPaG) to 400 psig (2757.904 kPaG), an anode water composition of about 0.1 mM to 50 mM bicarbonate; and Anode water pH greater than approximately 1.

[0164] In certain embodiments, the electrolyser may be constructed to favor product enriched molar ratios or concentrations as defined herein by using a carbon dioxide electrolyser having any one or any combination of the following characteristics: Relatively small nanoparticle catalysts (e.g., having, on average, a maximum dimension of about 0.1 nm to 15 nm); Gold as a cathode catalyst material; Cathode catalyst layer thickness of about 5um~20um, a cathode gas diffusion layer having a microporous layer (MPL); a cathode GDL having PTFE present at about 1 wt.% to 20 wt.%, or about 1 wt.% to 10 wt.%, or about 1 wt.% to 5 wt.%; a cathode GDL having a thickness of at least about 200 um; and A bipolar MEA having an anion exchange layer having a thickness of at least about 5 um. stoichiometric flow rate

[0165] Given that the molar flow rate may be determined, at least in part, by the current delivered to the cell, the molar flow rate may be tied to that current. As an example, the molar flow rate of carbon oxide in the input stream may be defined in terms of the flow rate per unit of reaction expected for a given current. As used herein, the term "stoichiometric" flow rate refers to a fraction or multiple of the flow rate of reactant carbon oxide required to fully utilize all the current at the cathode, assuming that the reduction reaction of carbon oxide is 100% efficient at the cathode for a given reaction. A carbon oxide flow rate with a stoichiometric value of "1" is the flow rate required to consume all the electrons provided at the cathode in a given reduction reaction at the cathode, and less. In other words, the stoichiometric flow rate is the amount of excess (or deficit) reactant present over (or below) the amount that could theoretically be reacted if the current efficiency for the given reaction was 100%.

[0166] Carbon dioxide reduction reaction (CO) produces carbon monoxide in an acidic environment. 2 +2H + +2e-→CO+H 2 For 1.O), a carbon dioxide flow rate with a stoichiometric value of 1 will provide 1 mole of carbon dioxide for every 2 moles of electrons provided by the cell. In other words, a cell with a current providing 2 moles of electrons / sec and a carbon dioxide flow rate providing 1 mole of carbon dioxide molecules / sec will have a stoichiometric flow rate of 1. With the same current and a flow rate of 0.5 carbon dioxide molecules / sec, the cell will have a stoichiometric flow rate of 0.5. And again with the same current but with a flow rate of 1.5 carbon dioxide molecules / sec, the cell will have a stoichiometric flow rate of 1.5. The molar flow rate required to achieve a stoichiometric flow rate of 1 can be calculated as follows: Stoichiometric flow rate (sccm) = [60 (s / min) * molar gas volume at STP (mL / mol)] / [Faraday constant (C / mol e-) * #e-'s / mol CO 2 ]*Amperes of current fed to electrolytic cell The total amperes of current can be calculated from the current density, the area of ​​the electrolyzer cells and the number of cells in the electrolyzer: Current in amperes = current density * area of ​​electrolyzer cell * number of cells

[0167] In one example, CO 2 500 mA / cm to perform the electrochemical reduction of CO 2 With a current density of 100 cm 2 The electrolyser has a total current of 50 A and the reaction calls for the production of 2 moles e- / mole CO, so the stoichiometric flow rate of 1 is: [60*22,413] / [9,6485*2]*50=348.4sccm In this example, a stoichiometric flow rate of 0.5 would be: 0.5*348.4=174.2sccm And the stoichiometric flow rates of the two are: 2*348.4=696.8sccm

[0168] In another example of a cell producing ethylene from carbon dioxide, 12 moles of electrons are required to reduce 2 moles of carbon dioxide to 1 mole of ethylene. The stoichiometric flow rates for a 3-cell 1500 cm2 electrolyser with a current density of 300 mA / cm2 are: [60*22,413] / [96,485*6]*1350=3,136sccm.

[0169] Various examples of the effects of specific electrolyzer designs and operating parameters on the molar ratio of gases in the cathode output stream are presented in U.S. Provisional Patent Application No. 63 / 263,567, filed November 4, 2021, which is incorporated by reference in its entirety herein.

[0170] In various embodiments, the oxygen produced at the anode of the carbon oxide electrolyzer is used in an integrated process. By way of example, the oxygen produced by the electrolyzer may be used in a partial oxidation gasification process, an aerobic fermentation process, an electrolysis process utilizing oxygen depolarized electrodes, and the like. In one example of an integrated scheme, a system having a Fischer-Tropsch reactor may utilize a carbon dioxide electrolyzer configured to produce syngas as an input to the Fischer-Tropsch reactor and oxygen as an input to a reactor for gasification of biomass, which also produces syngas for input to the Fischer-Tropsch reactor. 7. Integrated Scheme

[0171] Additional information regarding optional embodiments and / or system and / or method elements is provided below.

[0172] The product gas from the carbon oxide reactor of the present disclosure can be used in one or more downstream processes. For example, a carbon dioxide reactor of the present disclosure configured for synthesis gas production can be used to produce CO, H 2 , and / or CO 2 The heat generated during operation of the carbon oxide electrolyser may be used in one or more upstream and / or downstream processes requiring heating. Aerobic and anaerobic fermentation

[0173] This output stream can be fed to the input of a bioreactor where microorganisms (e.g., Clostridium autoethanogenum, Clostridium carboxydovorans, Clostridium ljungdahlii, Clostridium ragsdalei, Clostridium thermoaceticum, Clostridium thermoautotrophicum, Eubacterium limosum, Peptostreptococcus productus, Butyrivacterium methylotrophicum, Acetogens, Escherichia coli, etc.) produce CO, H, 2 , and / or CO and CO 2The energy of a portion of the carbon contained in the bioreactor is used to create one or more bioproducts (e.g., ethanol, acetic acid, butanol, butyric acid, methane, etc.). Unused carbon is extracted from the output of the downstream bioreactor (e.g., CO 2 as oxygen, optionally together with water vapor and / or other volatile compounds).

[0174] CO released as output of downstream bioreactor 2 can be optionally recycled back to the input of the carbon dioxide reactor of the present disclosure (e.g., to increase the carbon efficiency of bioproduct production, to control carbon dioxide reactor operation, etc.). In some embodiments, this CO 2 before entering (e.g., re-entering) the carbon dioxide reactor of the present disclosure. 2 For example, water vapor may be removed, any volatile products that would inhibit the carbon dioxide reactor function may be removed, and / or CO 2 may be pressurized to a level desired for operation of the carbon dioxide reactor of the present disclosure. The carbon dioxide leaving the bioreactor may be near atmospheric pressure and / or have any other suitable pressure, with typical carbon dioxide reactor pressures being 20 psi (137.8952 kPa) to 800 psi (5515.808 kPa), 50 psi (344.738 kPa) to 400 psi (2757.904 kPa), 100 psi (689.476 kPa) to 500 psi (3447.38 kPa), and / or any other suitable range. In some examples, water vapor is removed by a phase separator and / or a desiccant (e.g., a phase separator followed by a desiccant). In some examples, volatile products are removed by oxidation, adsorption onto a suitable adsorbent, and / or condensation. CO 2 Use a compressor to 2 The pressure of the CO2 reactor can be increased to a suitable pressure for the CO2 reactor. 2 It can be operated at 1000mV and can also be used to reduce CO from the downstream bioreactor. 2If not hindered by water vapor or any volatile compounds detected in the stream output, the system can be simplified to eliminate unnecessary purification and compression systems and processes.

[0175] For every liter of medium in the downstream bioreactor, a flow rate of gas from the output of the carbon dioxide reactor in the range of about 1 sccm to 1000 sccm, or about 1 sccm to 2000 sccm, or about 10 sccm to 500 sccm, or any other suitable range, may be desirable. 2 can be in the range of about 1 sccm to 2000 sccm, or about 10 sccm to 1000 sccm, or about 10 sccm to 500 sccm, or any other suitable range. For every liter of medium in the downstream bioreactor, the water vapor in the output gas stream exiting the bioreactor can be about 1% to 2% by volume of the stream, about 2% to 5% by volume of the stream, about 5% to 10% by volume of the stream, about 10% to 25% by volume of the stream, about 25% to 50% by volume of the stream, about 50% to 90% by volume of the stream, and / or any other suitable amount. Volatile products leaving the downstream bioreactor may constitute less than about 0.1% by volume of the stream, less than about 0.5% by volume, less than about 1% by volume of the stream, less than about 4% by volume of the stream, and / or any other suitable amount of the stream.

[0176] Some microbial processes can use the synthesis gas produced by the carbon dioxide reactor of the present disclosure. 2 , and optionally CO 2The syngas output stream of may be used as a feedstock for a downstream bioreactor, where microbial processes are carried out to create a wide range of useful compounds (examples include ethanol, acetic acid, butanol, butyric acid, acetone, and methane). The syngas stream itself may not contain all the nutrients required for the microorganisms in the downstream bioreactor to grow. The addition of other nutrients to the bioreactor may be required for the microorganisms to grow and produce products. Examples of suitable microorganisms include Clostridium autoethanogenum, Clostridium carboxydovorans, Clostridium ljungdahlii, Clostridium ragsdalei, Clostridium thermoaceticum, Clostridium thermoautotrophicum, Eubacterium limosum, Peptostreptococcus productus, Butyrivacterium methylotrophicum, Acetogens, and / or Escherichia coli.

[0177] One nutrient that can be particularly difficult to introduce into a downstream bioreactor is sulfur. Many microorganisms require sulfur for certain amino acid synthesis and enzymatic processes. The sulfur-tolerant carbon dioxide reactor of the present disclosure may simplify the addition of sulfur to the downstream bioreactor (e.g., in addition to providing syngas to the downstream bioreactor). 2 S, SO 2 , and / or other sulfur oxides (SO x Sulfur in the form of one or more sulfur-containing species (SCS), such as CO 2 It can be present in gases. 2 S may pass unchanged through the carbon dioxide reactor of the present disclosure and exit with the syngas output stream. 2 and / or SO x ) may pass through unchanged, and / or they may be converted into one or more other SCSs (e.g., H 2 S) and may be output with the syngas output stream. Thereafter, sulfur species (e.g., H 2 S, SO 2 , and / or SOx The syngas further comprising sulfur species can be fed to the input of a downstream bioreactor (e.g., no additional sulfur nutrition is required). The sulfur species concentration can be in the range of about 1 ppm to 10 ppm, about 5 ppm to 50 ppm, about 5 ppm to 100 ppm, about 10 ppm to 200 ppm, about 20 ppm to 1000 ppm, and / or any other suitable range.

[0178] In some embodiments, the carbon dioxide reactor can be coupled to one or more gas fermentation reactors (e.g., downstream of the carbon dioxide reactor, such as receiving one or more products of the carbon dioxide reactor). The method can optionally include controlling reactor operation based on this coupling, such as to optimize carbon efficiency and / or energy efficiency. Acetogens are most energy efficient with pure CO as an input, as seen in the energy balance shown in Table 1, and often also exhibit the highest selectivity towards the desired end products. However, there are cases where an integrated electrochemical gas fermentation system can be designed to utilize hydrogen-containing syngas for a number of reasons. Table 1 [Table 1]

[0179] Using CO for most or all of the electron transfer chemistry in the downstream bioreactor typically involves the use of CO 2 This results in the production of CO, which can then be vented into the output stream of the bioreactor. Typically, as the proportion of hydrogen in the syngas increases, the amount of CO 2 Less CO is produced. 2 By-products can be removed stoichiometrically above a certain ratio of hydrogen to carbon monoxide. For example, in the case of gas fermentation to ethanol, the ratio of CO:H is less than about 1:2. 2 The ratio of CO:H in the output stream of the carbon dioxide reactor of the present disclosure will typically result in the incorporation of all the input carbon into the ethanol end product. 2Adjusting the ratio allows the operator to get more H 2 Optimizing carbon efficiency by shifting towards production (e.g., CO 2 This can allow for optimizing energy efficiency by shifting towards lower CO2 emissions (minimizing CO2 emissions) and / or higher CO production. Monitoring input costs, such as time of day electricity rates or incentives for carbon utilization, can inform optimal operating parameters at any given time. Adjusting production in this manner can result in, for example, more ethanol production (e.g., higher CO) or more acetate production (e.g., higher H 2 ), the output can also be altered by driving the output towards the market price. Monitoring the market price of the output can inform optimal operating parameters at any given time (e.g., operating parameters are determined based on market price to optimize the market price of a product, or to optimize total profit from reactor operation, etc.).

[0180] However, the systems and / or methods may additionally or alternatively include any other suitable elements.

[0181] CO 2 A system consisting of an electrolyser and an aerobic fermentation reactor can be used to produce products such as proteins, polyhydroxyalkanoates, acetone, isopropanol, ethanol, and other products. 2 The electrolyzer receives the input CO 2 , water, and electricity, and CO 2 , hydrogen, unreacted CO 2 and outputs a stream of oxygen obtained from the water and a separate stream containing one or more carbon-based products, which may be CO, methane, ethylene, or mixtures of these compounds with other carbonaceous compounds.

[0182] The oxygen and carbon product stream can be fed to an aerobic gas fermentation system containing yeast, E. coli, or other microorganisms capable of metabolizing compounds in the gas stream to create desired products. The output of the aerobic gas fermentation reactor is a stream containing at least one bioproduct, which is typically in the liquid phase, and CO. 2 , water vapor, unmetabolized components of the gas feedstock, and trace hydrocarbons or H 2 The gas stream contains other volatile compounds produced during fermentation, such as CO, S, etc. 2 CO is produced in the same way as in the anaerobic fermentation process. 2 It can be recycled back to the inlet of the electrolyzer, but the O 2 If the concentration is greater than about 5%, 1%, or 0.25%, O 2 Removal may be necessary.

[0183] A variety of microbial metabolic pathways may be utilized for the gas fermentation reactor configured to receive the products of the carbon oxide electrolyzer. The design and operation of the electrolyzer will be tailored to the metabolic pathway and thus the required inputs of the pathway. One exemplary pathway is the Wood-Ljungdahl Pathway (WLP), which combines CO, CO 2 , formate, methanol, H 2, and / or have a set of biochemical reactions that can utilize other single carbon compounds to create acetyl coenzyme A (Acetyl-CoA). Acetyl-CoA is a molecule used as a source of carbon and energy for the microorganism. The Wood-Ljungdahl Pathway is a native metabolic pathway found in acetogenic microorganisms such as Clostridium ljungdahlii, but other microorganisms such as E. coli can be genetically engineered to have this pathway. Acetyl-CoA can be utilized by the microorganism to build cell mass, and / or it can be used as a starting molecule for other biochemical pathways to create other bioproducts such as acetone, ethanol, etc. The biochemical pathways that utilize Acetyl-CoA to create products can be derived from the organism, or they can be added by genetic engineering so that the microorganism will create the desired product.

[0184] A microorganism may utilize multiple metabolic pathways simultaneously. For example, sugars (e.g., glucose) may be metabolized by the microorganism through glycolytic or non-oxidative glycolytic pathways simultaneously with input to the WLP. Biomolecules (e.g., ATP / ADP, NADH / NAD+) may be produced in one metabolic pathway and used in another metabolic pathway.

[0185] WLPs do not generate ATP. If cells are depleted of ATP, they will favor acetate production from Acetyl-CoA. To generate ATP, cells must catalyze the synthesis of H through the Flavin-Based Electron Bifurcation Pathway to generate a proton gradient across their cell membrane. 2 The H in the gas stream can be used directly. This gradient can drive ATP production through ATP synthase. If the cell has ATP available, Acetyl-CoA can be converted to a wide range of desired products through natural or genetically engineered biochemical pathways. 2The ratio of CO to ATP determines the availability of ATP and can determine the carbon efficiency of a bioprocess.

[0186] In some embodiments, an aerobic fermentation process utilizing methane and carbon dioxide inputs produces 3-hydroxypropanoic acid. In some exemplary systems, a carbon oxide electrolyzer is configured to provide methane and carbon dioxide to a gas fermentation reactor that produces 3-hydroxypropanoic acid, among other products.

[0187] In another example, a carbon dioxide electrolyser is configured to produce outputs of carbon monoxide, carbon dioxide, and hydrogen, which may additionally be processed to have the ratios of these gases adjusted prior to delivery to a gas fermentation reactor that receives a sugar (e.g., glucose) as an input and reacts these components to produce acetone.

[0188] FIG. 4 shows a gas fermentation system 401 comprising a carbon oxide reduction electrolyzer 403 upstream from a gas fermentation bioreactor 405 and a recirculation unit 413 configured to recirculate the output of the bioreactor 405 to the input of the electrolyzer 403.

[0189] As shown, the electrolyzer 403 is configured to receive water and carbon oxides (carbon dioxide in this example) as reactants and electricity to drive the anode and cathode reactions. The input to the electrolyzer 403 is provided at a relatively high pressure (at least above atmospheric pressure). The anode reaction of the electrolyzer produces oxygen, which is used as an input to the bioreactor 405 only if aerobic fermentation is utilized. The output from the cathode side of the electrolyzer 403 includes unreacted carbon dioxide along with hydrogen gas and one or more carbon-containing products, such as carbon monoxide and / or methane. These outputs are provided at a relatively high pressure.

[0190] The system 401 is configured to transport the cathode output of the electrolyzer 403, optionally along with oxygen produced at the anode, to the bioreactor 405. The system 401 is configured to reduce the pressure of some or all of the electrolyzer products prior to or during delivery to the bioreactor 405. In certain embodiments, the system 401 includes a gas purification unit (not shown) between the electrolyzer 403 and the bioreactor 405. The gas purification unit is configured to adjust the concentration of the electrolyzer products before they enter the bioreactor 405. In some cases, the purification unit reduces the concentration of carbon dioxide in the gas stream. In some cases, the purification unit increases the concentration of carbon monoxide in the gas stream.

[0191] The bioreactor 405 is configured to convert the inputs, optionally along with other inputs such as sugars, into desired bio-products and by-products. In the example shown, the bio-products are relatively volatile or otherwise separable from the desired products and therefore may be passed to a recycle unit 413. In the embodiment shown, the system 401 is configured to transport carbon dioxide, water vapor, and possibly other volatile compounds at low pressure from the bioreactor to the recycle unit 413.

[0192] The recirculation unit 413 comprises one or more separation or removal units and a carbon dioxide compressor. In the embodiment shown, the recirculation unit 413 is configured to first receive the bioreactor steam output and pass them to the water and optionally oxygen separation unit 407. The output of the separation unit 407 may be a mixture of low pressure carbon dioxide and optionally volatile compounds. The recirculation unit 413 is further configured to pass the carbon dioxide and volatiles to the volatile compound removal unit 409, which removes the volatiles and outputs low pressure carbon dioxide. The recirculation unit 413 also includes a carbon dioxide compressor 411 configured to receive the low pressure carbon dioxide from the removal unit 409 and pressurize it to a suitable level for input to the electrolyzer 403.

[0193] In certain embodiments, the recirculation unit 413 includes one or more carbon dioxide capture units that include a sorbent material for capturing carbon dioxide during a first phase and releasing carbon dioxide during a second phase. The separation unit 409 may be configured to include or function in conjunction with such carbon dioxide capture units. Examples of such capture units are provided in the description of the direct air capture units described herein.

[0194] In the embodiment shown, the system 401 is configured to transport pressurized carbon dioxide from the recycle unit 413 to a point upstream from the cathode side inlet to the electrolyzer 403, at which point the carbon dioxide mixes with the pressurized feed carbon dioxide.

[0195] In certain embodiments, depending on the bioreaction being carried out, the carbon dioxide electrolyser located upstream from the bioreactor is configured to operate in (a) a hydrogen-rich product stream operating parameter regime as described herein, or (b) a high reduction product to hydrogen product stream operating parameter regime as described herein.

[0196] In various embodiments, the oxygen produced by the electrolyzer is used in an integrated process, such as a gasification process. For example, a system having a Fischer-Tropsch reactor may utilize an electrolyzer configured to receive carbon dioxide input from partial oxidation of hydrocarbons or from oxygen-consuming gasification of biomass. The oxygen may come from the anode side of the carbon dioxide electrolyzer and / or from an air separation unit.

[0197] 5 shows a system 501 including a carbon dioxide electrolyzer 503 configured to produce syngas. The system 501 also includes an aerobic fermentation reactor 505 configured to produce syngas. The system 501 is also configured to deliver oxygen produced at the anode of the electrolyzer 503 to the reactor 505. This oxygen may replace a portion of the oxygen normally provided from an alternative source, such as air separation, thus reducing the energy duty and scale of the air separation unit.

[0198] System 501 is configured to deliver syngas produced by electrolyzer 503, fermentation reactor 505, and potentially other sources to a downstream gasification or partial oxidation unit 507. System 501 may be configured to deliver some waste carbon dioxide from unit 507 to the cathode input stream of electrolyzer 503. Naphtha and fuel

[0199] As shown, the Fischer-Tropsch reaction may be characterized by the following general equation: (2n+1)H 2 +nCO->CH 2 n+nH 2 O

[0200] While the following discussion focuses on the Fischer-Tropsch reaction, one of skill in the art will appreciate that a class of related reactions may be utilized to produce liquid hydrocarbons and mixtures thereof (often collectively referred to as naphtha) from an input stream containing hydrogen and carbon monoxide. The class of reactions produces liquid hydrocarbon mixtures of various compositions depending on the composition of the input stream and the reaction conditions. Although the term Fischer-Tropsch is used herein, it should be understood to encompass any of a class of reactions that produce naphtha from a mixture containing carbon monoxide and hydrogen. Generally, such reactions are exothermic.

[0201] In various embodiments, the input stream to the Fischer-Tropsch reactor is a mixture of about 1:2 molar ratio of CO:H 2 CO / H 2 CO as a starting point to generate the mixture (or other Fischer-Tropsch input) 2 Some conventional electroless processes require two steps to use CO 2 +H 2 (Step 1) to produce CO 2 +H 2 The required 2:1 ratio of CO:H is obtained by using the reverse water gas shift (RWGS) reaction (step 2) to produce CO and water. 2 This results in a gas with a ratio close to 1:1. Therefore, in conventional processes, only after obtaining CO and hydrogen in the correct ratio can the Fischer-Tropsch reaction be utilized to produce liquid hydrocarbons. The aqueous shift (WGS) reaction and reverse aqueous shift reaction catalysts can generate metal dust that is harmful to downstream processes. Additionally, the aqueous shift reaction requires carbon monoxide and / or hydrogen feed.

[0202] Conventional synthesis gas processes sometimes use a CO+H reaction (rather than using a WGS and / or RWGS reaction or a carbon dioxide electrolyser, which may accentuate the production of CO). 2 Note that it can be used to produce the mixture directly. However, synthesis gas production often uses coal.

[0203] Fischer-Tropsch systems that utilize a carbon dioxide electrolyser as the carbon monoxide source have various advantages over the WGS or syngas routes. For example, unlike the RWGS reaction, the carbon dioxide electrolyser does not produce metal dust. In addition, compared to the RWGS reaction, the carbon dioxide electrolyser does not produce any CO 2 to CO.

[0204] However, carbon dioxide electrolysers require approximately the 1:2 molar ratio of CO:H required for the Fischer-Tropsch feed. 2 In some cases, the carbon dioxide electrolyser produces a CO-enriched stream. Thus, in some embodiments, a Fischer-Tropsch system, or any other system requiring a carbon monoxide and hydrogen mixture, may utilize a water electrolyser, or other hydrogen source, optionally working in combination with a carbon dioxide electrolyser. The water electrolyser is configured to create gaseous hydrogen to supplement the CO-enriched output of the carbon dioxide electrolyser. In some embodiments, a synthesis gas that is relatively rich in hydrogen may be produced as part of the co-electrolysis of carbon dioxide and water. The approximately 1:2 CO:H ratio of the FT reaction 2 To achieve the feed concentration, the system is 2 CO and H coming from the electrolyser through a gas separation unit 2 Using the sensed information as feedback, the operating conditions of the water electrolyzer may include a sensor configured to determine the concentration of CO:H. 2 H required to make the concentration 2 may be adjusted to deliver an amount of

[0205] Alternatively, suitable Fischer-Tropsch CO and H 2 A single CO2 source is used to generate the feed blend. 2An electrolyser may be used. This can be accomplished by operating the electrolyser to bias the output towards hydrogen production and / or by processing the electrolyser output to adjust its composition prior to delivery to the Fischer-Tropsch reactor. In certain embodiments, the carbon dioxide electrolyser includes an MEA that allows a relatively high percentage of H+ to reach the cathode. One way to facilitate a relatively high flux of H+ at the cathode is for the bipolar MEA to utilize a relatively thin cathode buffer layer and / or to utilize a cathode and cathode buffer layer with a polymer that has a relatively high H+ transport number. In another approach, the carbon dioxide electrolyser is constructed or operated to be carbon dioxide depleted. In certain embodiments, the electrolyser operates at a relatively high current density that tends to produce a higher ratio of hydrogen to carbon monoxide ratio. In some implementations, the electrolyser utilizes both a relatively high current density and a relatively low carbon dioxide feed to the electrolyser. Operation at a relatively high current density has the advantage of utilizing a relatively inexpensive electrolyser due to the cost of the equipment.

[0206] CO 2 The output of the electrolyzer is the product CO, by-product H 2 , unreacted CO 2 , and water vapor. The system may be configured to remove the water vapor and separate the unreacted carbon dioxide. The gas separation unit separates the CO and H 2 From CO 2 and / or otherwise separate CO and H 2 The system may be used to concentrate CO 2 Alternatively, the electrolytic cell may include a recirculation loop for recirculating water to the water inlet of the electrolytic cell. 2 It is then compressed and 2 The gas is returned to the inlet of the electrolyser. Examples of gas separation units are provided in Figures 19, 20, 23A-23D and the associated description.

[0207] The FT reactor may be operated above about 300 psi (2068.428 kPa) and between about 150° C. and 300° C. If the output of the carbon dioxide electrolyser and optional water electrolyser is not at the required pressure, the system may utilize a compressor to increase the feed gas pressure before entering the FT reactor. In the FT reactor, the CO-H 2 The mixture is converted into raw FT liquids and wax. The system is followed by an FT reactor to produce water, high melting point FT liquids, mid melting point FT liquids, and tail gas, volatile hydrocarbons, CO 2 , CO, and H 2 The FT liquids may be further upgraded via hydrocracking. Distillation and separation of different proportions of the FT liquids may result in jet fuel, diesel, and gasoline. The water from the FT reactor is filtered to remove impurities and CO 2 and / or may be fed into the water input of an optional water electrolyser.

[0208] FT systems are designed to reduce tail gas and / or volatile hydrocarbons (including, for example, methane) to CO 2 The system may be designed to recirculate the tail gas back to the electrolyzer. 2 This may be configured to separate the volatile hydrocarbons and unreacted CO and H into compressed and electrolyzer inlet and outlet gases. 2 The system may be configured so that these products are used to generate heat, energy, and CO 2 The gas may be designed or configured to be fed into a combustion reactor to produce CO. 2 Then, CO 2 The O2 from the electrolytic cell is fed to the inlet of the electrolytic cell. 2 may be used as an oxygen source for combustion, and pure CO 2 The combustion reactor may be operated in a "rich burn" mode utilizing an excess of fuel relative to oxygen to minimize the concentration of oxygen in the outlet stream. Water from the combustion reaction may be separated from the gas output, and CO 2It may be fed to the water input of an electrolyser or a water electrolyser.

[0209] Because the Fischer-Tropsch reaction is exothermic, it generates heat that can be used for other purposes in the system. Examples of such other uses include separations (e.g., distillation of light hydrocarbons) and reactions. In conventional systems, such reactions are endothermic reactions for the production of synthesis gas, such as reforming of fossil fuels, gasification of biomass, or production from carbon dioxide and hydrogen via reverse water gas shift. Thus, in conventional processes, all or most of the excess heat from the Fischer-Tropsch reaction is typically directed to synthesis gas production. However, in the present case of producing synthesis gas at low temperatures (e.g., below about 100°C) by processes such as carbon dioxide electrolysis, optionally with low-temperature water electrolysis, there is more excess heat from the Fischer-Tropsch reaction available for other processes such as carbon dioxide capture, thereby reducing the overall external heat requirements of the system and improving the carbon and energy efficiency of the carbon dioxide to fuel synthesis route.

[0210] In some embodiments, the tail gas is fed to a reformer where methane or other gaseous hydrocarbons react with water to produce a mixture of hydrogen and carbon monoxide, which is a form of synthesis gas. This can increase the yield of carbon from carbon dioxide in the liquid hydrocarbon product. Depending on the composition of the tail gas, the ratio of hydrogen to carbon monoxide can vary. In some embodiments, some amount of carbon dioxide and / or oxygen is present in the reformer. In many cases, the reforming reaction is endothermic. In some embodiments, heat to drive the endothermic reaction is provided, at least in part, from excess heat generated during the Fischer-Tropsch reaction. In some embodiments, heat to drive the endothermic reaction is provided, at least in part, from excess heat generated during the electrolysis of carbon dioxide by a carbon dioxide reduction electrolyzer. In some cases, some heat can be provided by combustion or direct electrical heat. To obtain heat from combustion, oxygen (optionally from the electrolyzer) can be fed to a furnace to improve efficiency, and carbon dioxide emissions can be captured and fed to the electrolyzer.

[0211] 6A shows a system 601 configured to produce liquid hydrocarbons where the primary or exclusive carbon source is a carbon oxide feedstock, such as one containing carbon dioxide and / or carbon monoxide. The system includes two main reactors: an electrolytic carbon oxide reduction cell or electrolyzer 611 and a Fischer-Tropsch reactor 621.

[0212] The electrolyzer 611 is connected to an electrical source and has one or more inlets for receiving reactants such as carbon dioxide and water. The electrolyzer 611 has one or more outlets on the anode side for removing oxygen and possibly trace impurities, and one or more outlets on the cathode side for removing reduction products including at least carbon monoxide. Other compounds leaving the cathode side may include hydrogen, water, and carbon dioxide.

[0213] The cathode outlet is connected to a purification unit, such as carbon monoxide purification unit 612, designed to separate or purify carbon monoxide from other components. In the embodiment shown, purification unit 612 has one outlet to provide carbon monoxide and another outlet to provide carbon dioxide, hydrogen, and possibly some carbon monoxide. In certain embodiments, carbon monoxide purification unit 612 can be an adsorbent-based unit, such as those presented in Figures 19, 20, and / or 23A-23D and associated description.

[0214] In system 601 , carbon dioxide, possibly along with some hydrogen and carbon monoxide, is recycled from the outlet of the CO purification unit 612 back to the inlet stream on the cathode side of the electrolyser 611 .

[0215] The Fischer-Tropsch reactor 621 is configured to receive carbon monoxide and hydrogen in a pressurized feed stream and at a specified composition. In the system 601, a compressor 624 compresses the carbon monoxide from the electrolyzer 611 along with hydrogen to an appropriate pressure for the Fischer-Tropsch reaction. The Fischer-Tropsch reaction may be carried out at temperatures between about 150° C. and 300° C. and at pressures between about one atmosphere and tens of atmospheres. Because the reaction is exothermic, little or no heat is provided to the reactor 621.

[0216] As mentioned, the input to the Fischer-Tropsch reactor may have a CO:H ratio of about n:(2n+1), where n is the length of the carbon atoms of the desired alkane product of the reaction. Thus, in various embodiments, the molar ratio of hydrogen to carbon monoxide provided to the reactor 621 is about (2n+1) to n. A hydrogen source 614 may be coupled to the outlet of the CO purification unit 612 or the inlet of the compressor 624 to provide the desired inlet composition ratio of hydrogen to carbon monoxide for the Fischer-Tropsch reaction. Alternatively, or in addition, the electrolyzer 611 may be designed or operated in a manner that produces a relatively high ratio of hydrogen to carbon dioxide. Reactor designs and operating conditions to achieve this ratio are described elsewhere herein. In some cases, a gas having a relatively high ratio of hydrogen to carbon monoxide is produced from a reforming reaction, such as a reaction using FT tail gas as an input.

[0217] As shown, system 601 is configured to provide the output of a Fischer-Tropsch reactor 621 to a separator 623 configured to separate MFTL and HFTL Fischer-Tropsch liquids from water and tail gas. As shown, the Fischer-Tropsch water may be recycled back to the input of the CO purification unit 612 and / or the input of the electrolyzer 611.

[0218] System 601 comprises a main recycle loop having a separation unit 631, a combustion chamber 632, and a water / gas separator 633. Separation unit 631 is configured to receive tail gas from separator 623 and remove carbon dioxide from the volatile hydrocarbons. System 601 is configured to recycle the carbon dioxide from unit 631 into the carbon dioxide feed stream to the electrolyzer 611.

[0219] System 601 is configured to transport volatile hydrocarbons from separation unit 631 to a combustion unit 632 configured to combust the hydrocarbons using an oxygen source from electrolyzer 611. System 601 is configured to transport combustion products from combustion unit 632 to a gas / water separator unit 633 configured to separate the carbon dioxide and water combustion products. System 601 is configured to transport water to an anode inlet of electrolyzer 611 and carbon dioxide to a cathode inlet of electrolyzer 611.

[0220] In certain embodiments, the carbon dioxide electrolyser located upstream from the Fischer-Tropsch reactor is adapted to operate in a hydrogen-rich product stream operating parameter regime as described herein, and / or a high reduction product vs. CO ratio as described herein. 2 It is configured to operate in a ratioed operating parameter regime.

[0221] In certain embodiments, the system 601 comprises one or more carbon dioxide capture units including a sorbent for capturing carbon dioxide during a first phase and releasing carbon dioxide during a second phase. The separation unit 631 and / or the gas / water separator unit 633 may be configured to include or function in combination with such carbon dioxide capture units. Examples of some principles of operation are provided in the description of the direct air capture units described herein. In some embodiments, the Fischer-Tropsch system is configured to provide waste heat generated from the exothermic Fischer-Tropsch reaction to the carbon dioxide capture unit.

[0222] 6B presents an exemplary system 634 for producing a liquid hydrocarbon mixture from a carbon dioxide input stream 635 using (a) a carbon dioxide electrolyzer 636 for producing carbon monoxide and hydrogen 637 and (b) a Fischer-Tropsch reactor 638 configured to receive the carbon monoxide and hydrogen and produce the liquid hydrocarbons. The carbon monoxide and hydrogen produced at least in part by the electrolyzer 636 may be used to purify or otherwise modify the syngas prior to delivery prior to entering the Fischer-Tropsch reactor (e.g., removing unreacted CO from the electrolyzer). 2 and compression and / or heating or cooling of the syngas stream) in a syngas processing element 640. Waste heat from the electrolyzer 636 can be used in purifying or modifying the syngas prior to entering the Fischer-Tropsch reactor. The system 634 is further configured to provide the processed gas from element 640 to a Fischer-Tropsch reactor 638, which can produce a mixture of light hydrocarbons and other components 642, which the system makes available to a product separation subsystem 643, which may include features to separate a tail gas 641 from one or more liquid hydrocarbon streams 644. In the embodiment shown, the system 634 includes a reformer 645 and is configured to provide the tail gas 641 to the reformer. The tail gas contains methane, which can react with water (optionally also included in the tail gas 641) via a methane reforming reaction to produce a hydrogen-rich mixture of carbon monoxide and hydrogen 647. System 634 is also configured to deliver mixture 647 to syngas processing element 640, which prepares the gas for introduction into Fischer-Tropsch reactor 638. The methane reforming reaction is endothermic. In some embodiments, excess heat from the reaction in Fischer-Tropsch reactor 638 is provided to reformer 645. In some embodiments, excess heat from the reaction in electrolyzer 636 is provided to reformer 645.

[0223] In the embodiment shown in FIG. 6B, system 634 is configured to provide oxygen 649, optionally from electrolyzer 636, to a furnace 651, which is configured to burn a fuel and generate additional heat for use in system 634 or elsewhere. CO 2 Direct air capture

[0224] In certain embodiments, the electrolytic carbon dioxide reduction system uses carbon dioxide received directly from air. The system for such embodiments uses direct air CO 2 The system includes a capture subsystem and a carbon dioxide reduction electrolyzer subsystem. The system captures and reduces the CO 2 However, CO is directly or indirectly introduced into the cathode side of the electrolyzer subsystem. 2 The device is configured to supply

[0225] Air-captured CO is often the only major feedstock. 2 The electrolysis system may be deployed in any location where there is space for the system components. In some deployments, the system occupies a relatively uncrowded area. In some deployments, the system occupies a densely populated area. In some embodiments, the system is deployed at least in part on a vehicle or vessel. For example, an air capture unit may be provided on a vehicle or vessel, while a carbon dioxide electrolyser may be provided at a port or offshore platform. In some cases, the deployment location is a location that has a ready supply of energy, e.g., solar and / or wind, abundant. In some cases, the deployment location is a desert. In some embodiments, the system is deployed in a location that is uncrowded, e.g., where there is an abundance of solar and / or wind power. 2The system is deployed in an extraterrestrial environment having a contained atmosphere. In some embodiments, the system is deployed on a large ship, such as a cargo ship, or a military vessel, such as an aircraft carrier. In some embodiments, the energy source is provided by a solar or wind farm associated with an offshore platform or port, while a carbon dioxide capture unit is provided on board a ship or other watercraft. A carbon dioxide electrolyser may be provided on board an offshore platform or port.

[0226] The system is designed to convert air or other gases into CO under specified conditions. 2 The capture subsystem may be designed to provide a CO 2 capture system. In certain embodiments, a fan, a vacuum pump, or simply wind may be used to capture the CO 2 capture system. 2 It is used to deliver air to the capture subsystem.

[0227] In certain embodiments, CO 2 The capture subsystem consists of two stages: Air to CO 2 In the first stage (phase 1), the air comes into contact with the adsorbent, which removes CO 2 and / or a second stage (Phase 2) in which heat, electricity, pressure, and / or humidity are applied to the adsorbent to release water. 2 Waste heat from the reduction electrolyzer is used.

[0228] In some implementations, CO 2 The capture subsystem is designed to capture CO 2 In various implementations, phase 1 is carried out at ambient or subambient conditions. In phase 2, temperature, electrical, pressure, and / or humidity swings are applied to capture the absorbed or adsorbed CO. 2 and optionally water is released.

[0229] In certain embodiments, the absorbent is 2 In one example, the adsorbent is heated to release CO 2For example, the mixture is heated from ambient temperature (e.g., about 20° C.-40° C.) to a temperature of at least about 70° C., and optionally to release water. In some cases, the temperature swing is from ambient to about 50° C.-1000° C., or from ambient to about 75° C.-200° C., or from ambient to about 600° C.-1000° C. In certain embodiments, the CO 2 Waste heat from the reduction electrolyzer is used. In one example, the adsorbent is 2 and optionally for a duration sufficient to remove a desired percentage of the water. The duration depends on the amount of adsorbent being treated, the amount of CO removed, and 2 and / or the proportion of water and the heat transfer to the adsorbent.

[0230] In certain embodiments, the absorbent is 2 As an example, the adsorbent is first exposed to dry air (e.g., air having up to about 50 mol % water, or up to about 30 mol % water, or up to about 5 mol % water) and then exposed to moisture vapor (e.g., air having at least about 75 mol % water, or at least about 90 mol % water, or about 100 mol % water).

[0231] In some embodiments, CO 2 The capture unit is 2 In certain cases, the electron swing carbon dioxide unit converts CO to a redox species such as a quinone (e.g., 2,6-di-tert-butyl-1,4-benzoquinone), 4,4′-bipyridine, or thiolate for carbon dioxide capture. 2 The faradaic adsorption system includes an electrochemical cell that utilizes the reductive addition of these redox agents. These redox agents may be provided in an organic electrolyte. In some cases, the electron swing adsorption system provides the carbon dioxide capture material on a solid support, such as a carbon nanotube support and / or a zeolite support. In some cases, the electron swing CO 2 The capture unit captures the CO 2 by providing heat (e.g., by Joule heating) to the absorbent and / or electrodes that retain CO2 is released.

[0232] CO 2 Depending on the configuration of the capture subsystem and its operating conditions, it can capture CO from air at high concentrations, e.g., about 90 mole % or more. 2 In some cases, CO 2 The capture subsystem captures CO at relatively low concentrations. 2 This is configured to generate CO 2 There is still enough for the reduction cell to operate.

[0233] For example, CO 2 Capture sorbents and associated subsystem components are available from Climeworks AG, Zurich, Switzerland, Global Thermostat, New York, NY, Carbon Engineering Ltd., Squamish, BC, Canada, Hydrocell, Finland, and Silicon Kingdom Holdings, Dublin, Ireland.

[0234] As shown, the captured and subsequently released CO 2 CO 2 In certain embodiments, water captured from the air is also a feedstock delivered directly or indirectly to the cathode side of the CO reduction electrolysis cell. 2 Used in electrolytic cell feedstock.

[0235] In certain embodiments, air-trapped CO 2 The electrolysis system may, for example, contain approximately 99 mol % CO 2 or more in a substantially pure stream from the direct air capture subsystem. 2 In a particular embodiment, the system is configured to operate in a manner that delivers CO to the electrolyzer. 2 Lower concentrations, for example, about 98 mol% CO 2 or more, or about 90 mol% CO 2 or even about 50 mol% CO 2or higher. In some cases, extremely low CO 2 A concentration of about 5 mol% to 15 mol% CO 2 is used as the feedstock. Such a concentration is still substantially higher than the atmospheric concentration of carbon dioxide, which is about 0.035 mol%. In certain embodiments, the system uses about 5 mol% to 15 mol% CO 2 mixed with another gas, such as air or nitrogen. 2 The device is configured to operate using concentrations.

[0236] Depending on the type of adsorbent used in the process, water can be absorbed by CO 2 In certain embodiments, CO 2 The output of the capture subsystem is humidified CO with a water concentration of approximately 0 mol% to 20 mol% water. 2 It is.

[0237] In certain embodiments, CO 2 The output of the capture subsystem is CO 2 , and other components in air such as nitrogen, oxygen, water, argon, or any combination of these. In all cases, CO 2 is present in a concentration greater than its concentration in air. In certain embodiments, CO 2 The output of the capture subsystem does not contain sulfur.

[0238] Direct Air Capture Unit and CO 2 The electrolyzer can be integrated in several ways depending on the type of air capture technology. Heat and mass transfer components are integrated into the entire air capture CO 2 It may be integrated in an electrolysis system.

[0239] For example, in some designs, CO 2 The reduction electrolyzer directly captures CO from the air capture subsystem. 2 The direct air capture subsystem is configured to receive and provide heat and / or humidity to the CO captured during phase 2 of the direct air capture subsystem utilizing a temperature swing desorption mechanism. 2The humidified electrolyzer product gas may release the CO captured during phase 2 of the direct air capture subsystem, which utilizes a humidity swing desorption mechanism. 2 can be used to release the

[0240] In certain embodiments, CO 2 The electrolyzer takes diluted CO as input. 2 (e.g., about 50 mol% CO 2 (hereinafter) designed or configured to receive

[0241] A direct air capture unit can be designed with multiple adsorbent tanks. 2 At least two different tanks are used to receive a continuous stream of CO (and optionally water) throughout the entire capture air 2 The electrolysis system operates at different stages of adsorption / desorption. For example, one adsorbent tank is CO 2 While the other captures air to capture CO 2 As each vessel continues through the adsorption / desorption cycle, CO 2 The adsorption tank that captures CO 2 The addition of multiple tanks at different times in the cycle increases the CO 2 Deliver a continuous stream of input CO to the electrolyzer. 2 and moisture and / or heat and / or vacuum.

[0242] Direct air capture units are CO 2 Desired volume of CO for downstream processes such as electrolyzers 2 The direct air capture subsystem can be sized to deliver a flow of 750 slpm CO. This can involve utilizing multiple adsorbent-containing vessels. For example, a direct air capture subsystem can be sized to deliver a flow of 750 slpm CO. 2 Such a subsystem may be configured to deliver 90% of the process CO 2The electrolyzer may be coupled to a 200-cell electrochemical stack consisting of a 1000 cm2 membrane electrode assembly operated at 300 mA / cm2 and 3 V / cell to produce 378 slpm CO and 42 slpm hydrogen, given the current efficiency vs. CO. 2 may be recycled back to the inlet to increase carbon efficiency. Operating continuously, the combined air capture and electrolyzer unit may produce approximately 675 kg / day of CO. Overall, in some designs, the air capture CO 2 The electrolyzer system is configured to produce at least about 100 kg / day of CO and / or other CO 2 In some designs, the CO2 trap is configured to output a reduction product. 2 The electrolyzer system is configured to produce at least about 500 kg / day of CO and / or other CO 2 and configured to output a reduction product.

[0243] In certain embodiments, the system utilizing direct air capture of the carbon oxide electrolyzer and optionally the carbon dioxide unit also includes a module configured to capture water from the air or atmosphere. In some embodiments, the module configured to capture water from the air utilizes solar energy and / or solar heat from photovoltaics along with a moisture absorbing material. In certain embodiments, the module configured to capture water is an atmospheric dehumidifier, such as a hydropanel (e.g., available from Zero Mass Water, Inc., Scottsdale, AZ).

[0244] Figure 7A shows direct air CO 2 Capture subsystem 703 and CO 2 Air Capture CO with Reduction Electrolyzer Subsystem 705 2 7 shows an electrolyzer system 701. As shown, a direct air CO 2 The capture subsystem 703 may be configured to perform, during adsorption phase 1, a process in which the capture subsystem 703 performs, for example, atmospheric conditions, optionally with humidity (approximately 0.035 mol % CO 2 ) under CO 2 It receives air containing most of the CO 2The device is configured to emit air with much of the moisture removed, and optionally with much of the humidity removed.

[0245] Direct Air CO 2 The capture subsystem 703 captures CO 2 and optionally water. 2 , and optionally water as inputs 2 The CO released from the direct air capture subsystem 703 during phase 2 is provided to the electrolyzer 705. 2 is provided to the cathode side of the electrolyzer 705. As shown, optional CO 2 Purification unit 707 is a direct air CO 2 Interposed between the capture subsystem 703 and the electrolyzer 705. Direct air CO 2 The water optionally provided by the capture subsystem 703 is used to capture the (CO 2 It may be directed to the cathode side (as moisture in the feedstock) or to the anode side (as a reactant).

[0246] In the embodiment shown, the electrolytic cell 705 is a (CO 2 The electrolyzer 705 is configured to receive electricity (to drive the reduction and anodic oxidation reactions). The electrolyzer 705 also converts excess heat from the electrolysis reactions directly into air CO 2 capture subsystem 703 for phase 2 (CO from the adsorbent) 2 The actuator is configured to drive a first electrode (emission).

[0247] CO 2 The electrolyzer 705 generates oxygen (the anode reaction product when water is the reactant) and one or more CO 2 The reactor is configured to output reduction products, which may include CO and / or other carbon-based products as described elsewhere herein. 2 The product streams of the electrolyzer 705 are hydrogen, CO 2 As shown, the system 701 may contain hydrogen, CO 27. The electrolyzer output is configured to provide to a separation unit 709 configured to separate CO and / or other carbon-based electrolysis products from the humidified CO from the separation unit 709. In the embodiment shown, the system 701 separates the humidified CO from the separation unit 709. 2 Direct air CO 2 The capture subsystem 703 is configured to deliver the captured signal to the capture subsystem 703.

[0248] In certain embodiments, the carbon oxides are captured on board the vessel or vehicle as the fuel is burned. The fuel may be used, for example, in an internal combustion engine to propel the vessel or vehicle. The fuel may be used for other purposes such as heating, electricity generation, etc. The captured carbon oxides are provided to the cathode of a carbon oxide electrolyzer, which produces a reduced product that is used directly, stored, or converted by downstream processing into a different product (e.g., a chemical, polymer, or fuel). In embodiments where the electrolyzer and associated downstream components are configured to produce fuel, the resulting fuel may be utilized on the original vessel or vehicle, or on one or more other vessels or vehicles. In some implementations, both the carbon oxide capture subsystem and the electrolyzer, as well as the optional downstream processing subsystem, are provided on board the vehicle or vessel. In some implementations, only the carbon oxide capture subsystem is provided on the vehicle or vessel. In some cases, the captured carbon oxides are temporarily stored on board the vehicle or vessel. For example, carbon dioxide may be stored in one or more tanks, pressurized containers, tankers, etc. In other cases, the captured carbon oxides are stored outside the vehicle or vessel, such as in an underground reservoir, tanker ship, offshore platform, etc. In some cases, the stored carbon oxides are offloaded from the vessel or vehicle where it is provided to a carbon oxide electrolyzer. Examples of locations where the stored carbon oxides may be offloaded and / or where the electrolyzer is located include chemical plants, ports, and offshore platforms, including those located in proximity to green energy sources such as wind or solar energy. Examples of vessels and vehicles include ships, trucks, buses, cars, aircraft, and other vehicles.

[0249] 7B illustrates an example in which carbon dioxide is captured from fuel combustion products on board a vessel or vehicle. As shown, a vessel 720 produces carbon oxides 721, which are stored in a storage medium 722 prior to being fed to a carbon oxide electrolyzer 723. The electrolyzer and associated downstream chemical processing equipment may produce chemical products 725 and / or fuel 726. In the case of a fuel, the fuel may be utilized by the vehicle or vessel.

[0250] In certain embodiments, depending on the needs of the system, direct air CO 2 The carbon dioxide electrolyser, located downstream from the capture subsystem, comprises: (a) a high reduction product vs. CO electrolyzer as described herein; 2 (b) a hydrogen-rich product stream operating parameter regime as described herein; or (c) a high reduction product to hydrogen product stream operating parameter regime as described herein. Polycarbonate

[0251] Certain aspects of the present disclosure relate to a polycarbonate production system that includes (a) one or more carbon oxide electrolyzers configured to produce one or more carbon-containing products and (b) one or more polycarbonate synthesis reactors configured to produce polycarbonate polymers from carbon-containing compounds obtained directly or indirectly from the products of the one or more electrolyzers.

[0252] In certain embodiments, at least one electrolyzer in a polycarbonate production system comprises a membrane electrode assembly (MEA) that optionally comprises a polymer electrolyte membrane (PEM), such as a cation exchange polymer membrane. Unless otherwise specified or clear from the context, references herein to carbon oxide electrolyzers, including carbon dioxide reduction electrolyzers, encompass MEA-based electrolyzers, specific embodiments of which are described elsewhere herein.

[0253] In certain embodiments, a polycarbonate production system includes a carbon dioxide reduction electrolyzer configured to produce carbon monoxide, and one or more other subsystems that convert the carbon monoxide to one or more intermediates for subsequent reaction to produce a polycarbonate polymer.

[0254] In various embodiments, the direct output of the carbon oxide electrolyzer is converted to one or more intermediate compounds, such as phenols, ketones, and / or organic carbonates, which are reacted to produce polycarbonates. Conversion to such intermediate compounds may be by any of a variety of processes. Examples include Fischer-Tropsch reactions, gas fermentation reactions, and cracking reactions.

[0255] In a gas fermentation subsystem embodiment, a carbon dioxide electrolyser is used to produce carbon monoxide, and optionally hydrogen, which is then used in a downstream gas fermentation process to produce one or more intermediate compounds for producing the polycarbonate polymer. Examples of these intermediate compounds include ketones (e.g., acetone), light hydrocarbons, and phenols.

[0256] In a Fischer-Tropsch subsystem, which may correspond to other embodiments described herein, carbon monoxide and hydrogen from the carbon dioxide electrolyzer are reacted to form naphtha or other light hydrocarbon products.

[0257] In certain embodiments, one or more subsystems for producing intermediates produce or are configured to produce diol compounds, such as bisphenol A. Other diol polycarbonate intermediates may be produced in alternative embodiments, including bisphenols other than bisphenol A. In certain embodiments, the subsystem comprises a reactor for producing phosgene from carbon monoxide and chlorine. Carbon monoxide may be produced from a carbon dioxide reduction electrolyzer.

[0258] In certain embodiments, the polycarbonate synthesis system utilizes at least two separate electrolysis modules that may share some common electrical infrastructure, such as a common electrical bus. In certain embodiments, the two separate electrolysis modules are two separate electrolytic carbon oxide reduction electrolyzers. As an example, the first carbon oxide reduction electrolyzer is a carbon dioxide electrolyzer designed, configured, or operative in a manner to produce carbon monoxide and optionally hydrogen gas, and the second carbon oxide reduction electrolyzer is a carbon dioxide electrolyzer designed, configured, or operative to produce at least one product compound having at least two carbon atoms, such as ethylene, or a ketone, such as acetone. In some implementations, the first electrolyzer comprises a cathode having a precious metal catalyst, such as gold, and the second electrolyzer comprises a cathode having a transition metal catalyst, such as copper. As disclosed elsewhere herein, MEA-based carbon oxide electrolyzers can be used to produce separate products (e.g., CO vs. C). 2 The endonuclease may have a variety of designs or configurations that allow for the production of a desired compound.

[0259] In certain embodiments, the first electrolysis module is a carbon oxide reduction module and the second electrolysis module is a chlorine generation module, such as a chloralkali cell. These two modules may share a common electrical infrastructure. In some embodiments, the chlorine generation module is a conventional chloralkali module configured to receive chloride salts and water as inputs and to produce chlorine gas and hydrogen gas as outputs. In some embodiments, the chlorine generation module comprises an oxygen reduction chloralkali cell configured to receive chloride salts in an electrolyte, receive oxygen gas at a cathode (oxygen depolarized cathode), and produce chlorine gas at the anode and water at the cathode. Such oxygen reduction chloralkali cells operate efficiently and consume less electrical energy than conventional chloralkali cells. However, they require a source of oxygen. In some implementations, the polycarbonate generation system is configured such that oxygen gas produced as the anode of the carbon oxide reduction cell is provided to the cathode of a chlorine generation cell configured to reduce oxygen. In some implementations, the polycarbonate production system is configured to provide water produced by the oxygen reducing chloralkali cell to the carbon oxide abatement cell as humidification for the anode water or the carbon oxide feed stream.

[0260] In certain embodiments, such as that shown in FIG. 8, system 801 includes an electrolysis cell, such as a chloralkali cell, for producing chlorine. In some implementations, system 801 is configured to feed oxygen from electrolyzer 803 to a cathode of a chloralkali cell that includes an oxygen-depolarized cathode. In some implementations, system 801 is configured to feed oxygen from a water electrolyzer to an oxygen-depolarized cathode of a chloralkali cell. System 801 may be configured to provide hydrogen from the water electrolyzer to a Fischer-Tropsch reactor, a gas fermentation reactor, or other reactor used in the production of polyol precursors. Oxygen from electrolyzer 803 or other electrolyzers may be used in place of oxygen from other sources, such as air separation.

[0261] In certain embodiments, the alkaline by-product of the chloralkali cell (e.g., sodium hydroxide) is provided as a feedstock to a supplemental chemical production system, such as a formate production system, including, by way of example, a formate production system utilizing a carbon oxide electrolyzer.

[0262] In certain embodiments, polycarbonates utilize bisphenol A linkages in the polymer backbone, and indeed most system and method examples presented herein describe bisphenol A, along with phosgene, as the polycarbonate precursor. However, for some applications, other diols are used in place of bisphenol A. Examples include other linear or cyclic unsaturated diols, as well as diphenols and other bisphenols. In the examples described herein, when reference is made to bisphenol A, it should be understood that it is intended that other bisphenols may be utilized as appropriate for the desired polycarbonate end product. It should also be understood that appropriate system and method modifications may be utilized to replace the phenol-producing module with a module configured to produce a phenol derivative or analogue, and / or to replace the acetone-producing module with a module configured to produce other ketones.

[0263] The polycarbonate synthesis reaction may involve treatment of bisphenol A with sodium hydroxide, which deprotonates the hydroxyl groups of bisphenol A. (HOC 6 H 4 ) 2 CMe 2 +2NaOH →Na 2 (OC 6 H 4 ) 2 CMe 2 +2H 2 O

[0264] Diphenoxide (Na 2 (OC 6 H 4 )2 CMe 2 ) reacts with phosgene to give a chloroformate which is then attacked by another phenoxide. The net reaction from the diphenoxide is: Na 2 (OC 6 H 4 ) 2 CMe 2 +COCl 2 →1 / n[OC(OC 6 H 4 ) 2 CMe 2 ] n +2NaCl

[0265] In various embodiments, at least one carbon dioxide reduction electrolyzer used in the polycarbonate production system is designed or configured to operate in a manner that produces a significant proportion of hydrogen in addition to carbon monoxide. In certain embodiments, the carbon dioxide electrolyser located upstream of the diol production reactor is adapted to operate under (a) a hydrogen-rich product stream operating parameter regime as described herein, and / or (b) a high reduction product vs. CO ratio as described herein. 2 It is configured to operate in a ratioed operating parameter regime.

[0266] Electrolyzers for producing carbon monoxide often utilize a cathode catalyst comprising a precious metal such as gold. Such catalysts favor the production of carbon monoxide over hydrogen-containing compounds such as methane, ethylene, formic acid, etc. Electrolyzers configured to provide a hydrogen-rich product may utilize a design that (a) depletes the cathode of the carbon dioxide reactant and / or (b) allows a relatively high flow rate of hydrogen ions to be transported from the anode (where hydrogen ions are produced) to the cathode. Electrolyzers that can operate with relatively low carbon dioxide inputs may have flow fields or gas diffusion components that limit carbon dioxide from reaching the active sites on the electrolyzer cathode. Electrolyzers that can operate with a relatively high flow rate of hydrogen ions to the cathode may have an MEA with a cation conducting polymer and / or mixed ion conducting polymer at the cathode, and / or a cathode buffer layer, if used. In some cases where the MEA includes an anion conducting cathode buffer layer, the layer is designed to be relatively thin and / or have a relatively high hydrogen ion transport number.

[0267] FIG. 8 shows a general representation of a system for producing polycarbonate polymers using a carbon dioxide reduction electrolyzer. As shown, polycarbonate production system 801 includes a carbon dioxide reduction electrolyzer 803 configured to receive carbon dioxide and water as reactants and electricity to drive anodic and cathodic reactions that produce oxygen and one or more carbon dioxide reduction products. In the embodiment shown, carbon dioxide reduction reactor 803 is configured to produce at least carbon monoxide as one reduction product. System 801 is specifically configured to deliver carbon monoxide from electrolyzer 803 to phosgene production reactor 805. Reactor 805 additionally includes an input for receiving chlorine gas. The chlorine gas and carbon monoxide react in phosgene reactor 805 to produce phosgene as an output. System 801 is further configured to deliver phosgene from phosgene reactor 805 to polycarbonate synthesis reactor 807.

[0268] In certain embodiments, the carbon dioxide electrolyser located upstream from the phosgene generation reactor is adapted to operate in a carbon dioxide electrolyser that is operable to react with the phosgene generation reactor in a manner that utilizes (a) a high reduction product to hydrogen product stream operating parameter regime as described herein, and / or (b) a high reduction product to CO 2 It is configured to operate in a ratioed operating parameter regime.

[0269] As shown, the polycarbonate synthesis reactor 807 also has an input for receiving a diol input material. The diol input may be generated by a variety of methods, including via a reactor not shown in this figure. Alternatively, as shown here, the system 801 includes a diol synthesis reactor or subsystem 809 configured to receive the carbon dioxide reduction product from the electrolyzer 803. In various embodiments, these electrolyzer reaction products include carbon monoxide and hydrogen. In some cases, these electrolyzer products include C 2 or higher products such as acetone or formaldehyde. In certain embodiments, reactor or subsystem 809 is configured to receive and react inputs from sources other than electrolytic cell 803. These other inputs may include, for example, phenolic compounds such as bisphenol. System 801 is also configured to transport diols produced by diol synthesis reactor or subsystem 809 to polycarbonate synthesis reactor 807. Within polycarbonate synthesis reactor 807, the diols and phosgene react to produce polycarbonate polymer. In the embodiment shown, polycarbonate end product is available from polycarbonate synthesis reactor 807 via an outlet.

[0270] It should be understood that a polycarbonate production system such as that shown in Figure 8 may include additional or alternative types of modules not shown in this figure. These may include, for example, one or more purification units, such as a carbon monoxide purification module, heaters, compressors, condensers, and other chemical reactors. Examples of gas purification units for use in the system of Figure 8 or any other polycarbonate production system described herein are provided in Figures 19 and 20 and the associated description.

[0271] Types of reactors that can be used to produce phenol, ketone, and organic carbonate intermediates include gas fermentation reactors, Fischer-Tropsch reactors, and oxidative carbonylation reactors. In some cases, particularly due to the reaction pathways used to form with phenolic compounds, system 801 may include multiple intermediate modules or reactors. In one example, system 801 includes one module for producing simple liquid hydrocarbons, another module for cracking those hydrocarbons to produce aromatics and other unsaturated carbon-containing compounds, and / or one or more additional intermediate reactors for producing ketones, organic carbonates, and / or phenol derivatives. In various embodiments, these intermediate modules for producing ketones and / or phenols utilize a combination of carbon monoxide and excess hydrogen produced by carbon dioxide reduction electrolyzer 803. Examples of various integrated systems for producing polycarbonates are presented in U.S. Provisional Patent Application No. 63 / 263,567, filed November 4, 2021, which is incorporated herein by reference in its entirety. Formate

[0272] Alkali metal formates have many uses, including as enzyme stabilizers in liquid detergents. The enzymes may be lipases, amylases, proteases, etc. Other formates, such as alkaline earth metal formates, also have many uses. In certain embodiments, the formate generation system utilizes a carbon dioxide reduction electrolyzer to convert carbon dioxide to carbon monoxide, which is processed to produce alkali metal formates. In various embodiments, the metal formates are produced by contacting a metal hydroxide with carbon monoxide. The contacting may occur in a liquid (e.g., aqueous) or solid medium.

[0273] 9 illustrates an exemplary formate production system 901 that includes a carbon dioxide reduction electrolyzer 903, a formate production reactor 905, and various downstream formate recovery units. The electrolyzer 903 is configured to receive oxygen and carbon dioxide as reactants and electricity to drive the reduction of carbon dioxide to produce carbon monoxide. The system 901 is configured to transport the carbon monoxide from the electrolyzer 903 to the formate production reactor 905, where the carbon monoxide reacts with a hydroxide (e.g., sodium hydroxide, potassium hydroxide, cesium hydroxide, or calcium hydroxide) to produce dissolved metal formate. The reactor 905 is configured to receive not only the carbon monoxide from the electrolyzer 903, but also the metal hydroxide, a solvent, and a catalyst. The reactor 905 may be a stirred tank reactor.

[0274] In certain embodiments, the carbon dioxide electrolyser located upstream from the metal formate production reactor is adapted to operate in a carbon dioxide electrolyser that is operable to produce hydrogen at a rate of 10000 stoichiometric amounts of hydrogen peroxide at a rate of 1 ... 2 It is configured to operate in a ratioed operating parameter regime.

[0275] The system 901 is configured to transport the formate-containing solution from the reactor 905 to a degassing unit 907, which during operation removes gases from the formate solution. Such gases include unreacted carbon monoxide. The system 901 is further configured to transport the degassed formate solution from the unit 907 to an evaporator 909 configured to at least partially evaporate the solvent from the formate solution and produce a slurry or other liquid-solid mixture containing precipitated metal formate. The system 901 additionally includes a filtration unit 911 configured to receive and filter the output of the evaporator 909. The output of the filtration unit 911 includes concentrated solid metal formate. The system 901 additionally includes a solvent washing unit 913 configured to wash the solid formate-containing output of the unit 911 by contacting the formate material with a solvent. The system 901 is further configured to transport the filtered and washed solid formate from the unit 913 to a dryer 915 configured to dry the solid formate and produce the solid metal formate in a final form. The dryer 915 is configured to receive a drying gas, such as nitrogen or carbon dioxide, along with the heat. In certain embodiments, the dryer 915 is configured to receive waste heat from the electrolyzer 903. In certain embodiments, the dryer 915 is configured to receive carbon dioxide from the electrolyzer 903 or from an inlet stream to the electrolyzer 903. In some implementations, externally provided dry carbon dioxide is passed from the dryer 915 to the input stream for the electrolyzer 903.

[0276] In some implementations, the formate produced by system 901 is an alkali metal formate, such as sodium, potassium, or cesium formate, or an alkaline earth formate, such as calcium or barium formate. In some cases, system 901 is configured to produce formic acid from the metal formate by using a reactor configured to contact the metal formate with an acid, such as hydrochloric acid.

[0277] In some embodiments, metal formates are produced by contacting carbon monoxide produced by a carbon dioxide electrolyzer with solid or slurry form metal hydroxides. For example, sodium formate may be produced by contacting solid sodium hydroxide with a carbon monoxide stream. The reaction may be expressed as NaOH(s)+CO(g)->NaCOOH(s). The solid hydroxide may be provided in various forms, such as powder. In some cases, to increase the surface area of ​​the hydroxide available for reaction, it is optionally ground, powdered, or otherwise reduced in particle size during reaction with carbon monoxide. For example, the solid hydroxide may be ground in a ball mill autoclave during contact with carbon monoxide. In some cases, optionally during the reaction in the autoclave, the solid hydroxide is contacted with carbon monoxide at a temperature of at least about 200° C. (e.g., about 230° C. to 300° C.) and / or at a pressure of at least about 2 bar (200 kPa) (e.g., about 5 bar (500 kPa) to 10 bar (1000 kPa)). In some embodiments, the formate production reaction in the autoclave has a residence time of at least about 15 minutes to 60 minutes, or about 20 minutes to 40 minutes.

[0278] In some metal formate syntheses, carbon monoxide is provided to a reactor (eg, an autoclave with solid metal hydroxide) at a concentration of at least about 0.5 mole fraction, or at least about 0.8 mole fraction, or at least about 0.9 mole fraction. Ethylene glycol

[0279] 10A and 10B show a process for preparing ethylene glycol (monoethylene glycol or MEG). As shown in FIG. 10A, MEG production system 1001 includes a carbon oxide electrolyzer 1003, an ethylene oxide production reactor 1005, and a MEG production reactor 1007. The electrolyzer 1003 is configured to produce ethylene. The system 1001 is configured to deliver ethylene from the electrolyzer 1003 to the ethylene oxide production reactor 1005. Optionally, the system 1001 is additionally configured to deliver oxygen from the electrolyzer 1003 to the reactor 1005. Regardless of the oxygen source, the reactor 1005 is configured to react ethylene and oxygen to produce ethylene oxide.

[0280] In a particular embodiment, the reactor 1005 is a direct ethylene oxide reactor designed or configured to produce ethylene oxide directly from ethylene and oxygen. In this approach, ethylene and compressed oxygen may be fed into a multi-tube catalytic reactor (one example of reactor 1005). During operation of such a reactor, the mixture is passed over a silver oxide catalyst supported on a porous carrier at about 200° C.-300° C. and about 10 bar (1000 kPa)-30 bar (3000 kPa). The reaction is exothermic, and the removed heat can be used elsewhere in the system. The system 1001 may be configured to cool the gases from the reactor 1005 and pass them through a scrubber, where the ethylene oxide is absorbed as a dilute aqueous solution.

[0281] System 1001 may be configured to deliver ethylene oxide from reactor 1005 to an ethylene glycol production reactor 1007. Reactor 1007 may be configured to react ethylene oxide and water to produce ethylene glycol. The reaction may be catalyzed by acid or base or carried out at neutral pH and at elevated temperature. In certain embodiments, system 1001 is configured to provide heat from electrolyzer 1003 and / or ethylene oxide production reactor 1005 to MEG reactor 1007.

[0282] As shown in FIG. 10B, the MEG generation system 1011 includes a carbon dioxide electrolyzer 1013 and a MEG generation reactor 1017. The electrolyzer 1013 is designed or configured to generate carbon monoxide and hydrogen. The system 1011 is configured to deliver these outputs, along with oxygen (optionally from the electrolyzer 1013), to the reactor 1017, where the reactants react to generate ethylene glycol. The reactor 1017 may be configured to generate ethylene glycol from these reactants via a two-stage process that generates dimethyl oxalate as an intermediate from a reaction pathway involving methanol, nitrous oxide, and carbon monoxide. The generation of dimethyl oxalate may utilize a palladium catalyst. The reactor 1017 may be configured to perform a second stage by reacting dimethyl oxalate with hydrogen gas using a copper catalyst to generate ethylene glycol. In this process, only carbon monoxide, hydrogen, and oxygen are consumed. The hydrogen for the reaction may come from any suitable source. A typical hydrogen source is shown as hydrogen generator 1019 in system 1011. In certain embodiments, hydrogen generator 1019 is a water electrolyzer. In certain embodiments, hydrogen generator 1019 is a reactor configured to perform an aqueous shift reaction. In certain embodiments, hydrogen is produced from a fossil fuel and the carbon dioxide product is optionally recycled to the electrolyzer 1013. System 1011 may be configured to provide excess oxygen from the electrolyzer 1013 to a combustion reactor.

[0283] In certain embodiments, a carbon dioxide electrolyser located upstream from the MEG production reactor is configured to operate in a hydrogen-rich product stream operating parameter regime as described herein, and / or a high reduction product vs. CO regime as described herein. 2 It is configured to operate in a ratioed operating parameter regime. Polyethylene terephthalate

[0284] Figure 11 provides a schematic diagram of a system 1101 that may be utilized to produce the polymer polyethylene terephthalate. One process or group of processes utilizes a carbon oxide electrolyzer 1103 configured to produce ethylene. Another process or group of processes utilizes a carbon dioxide electrolyzer 1113 configured to produce carbon monoxide and hydrogen.

[0285] System 1101 is configured to implement a PET production pathway that includes an electrolytic cell 1103. As shown, system 1101 additionally includes an ethylene oxide production reactor 1105 and an ethylene glycol production reactor 1107, which may be configured and arranged similarly to system 1001 of Figure 10A. System 1101 is configured to deliver ethylene glycol to PET production reactor 1109, which is configured to react ethylene glycol with phthalic acid to produce PET polymer.

[0286] One version of system 1101 for producing both ethylene glycol and phthalic acid includes an electrolyzer 1113 configured to produce carbon monoxide and hydrogen. The ethylene glycol production pathway is configured to react these products, possibly with the addition of additional hydrogen from a source 1119 in an MEG production reactor 1117. System 1101 is configured to provide MEG from reactor 1117 to a PET production reactor 1109. This version of system 1101 utilizing electrolyzer 1113 optionally does not include components for the MEG pathway utilizing electrolyzer 1103, ethylene oxide production reactor 1105, and MEG synthesis reactor 1107.

[0287] The version of the system 1101 utilizing the electrolyzer 1113 may include a reactor for producing terephthalic acid from the carbon monoxide and hydrogen produced by the electrolyzer 1113. The reactor may produce naphtha and p-xylene as intermediates. In the embodiment shown, a Fischer-Tropsch or gas fermentation reactor 1121 is configured to produce naphtha from the carbon monoxide and hydrogen output by the electrolyzer 1113. The reactor 1121 may be designed or configured as described elsewhere herein. The naphtha cracking reactor 1123 is configured to crack the naphtha and produce p-xylene. In certain embodiments, the system 1101 is configured to supply excess heat and / or hydrogen produced by the cracker 1123 to the reactor 1121. The PTA reactor 1125 is configured to convert p-xylene to terephthalic acid.

[0288] In certain embodiments, the carbon dioxide electrolyser located upstream from the Fischer-Tropsch reactor is adapted to operate in a hydrogen-rich product stream operating parameter regime as described herein, and / or a high reduction product vs. CO ratio as described herein. 2 It is configured to operate in a ratioed operating parameter regime.

[0289] In some versions of system 1101, the carbon oxide reduction electrolyzer is configured to directly produce ethylene glycol (MEG) by electrolysis. In such versions, the electrolyzer would replace or supplement another MEG production route, such as one utilizing reactor 1107 or reaction 1117. Some versions of system 1101 utilize a reactor configured to directly convert carbon monoxide from reactor 1113 to p-xylene along with hydrogen. This version of system 1101 is configured to transport such p-xylene to PTA reactor 1125. Acetic acid

[0290] 12 shows a schematic of a system 1201 for producing acetic acid from carbon monoxide and hydrogen produced by a carbon dioxide electrolyser 1203. The system 1201 comprises a methanol production reactor 1205 configured to react carbon monoxide and hydrogen to produce methanol. The reactor 1205 may be configured in the manner of a conventional methanol synthesis reactor utilizing synthesis gas.

[0291] In certain embodiments, the carbon dioxide electrolyzer located upstream from the methanol production reactor is configured to operate in a hydrogen-rich product stream operating parameter regime as described herein, and / or in a high reduction product vs. CO regime as described herein. 2 It is configured to operate in a ratioed operating parameter regime.

[0292] System 1201 also includes an acetic acid production reactor 1207 configured to react methanol and purified carbon monoxide to produce acetic acid. Reactor 1207 may be configured to perform methanol carbonylation using, for example, a metal carbonyl catalyst. In certain embodiments, system 1201 includes a carbon monoxide purification unit 1209 configured to produce purified carbon monoxide. The carbon dioxide purification unit may be designed in a manner described elsewhere herein (e.g., in the manner of the units in Figures 19 and 20). Isocyanates

[0293] FIG. 13 illustrates generally a system 1301 configured to produce diisocyanates from electrolytically generated carbon monoxide.

[0294] System 1301 may be configured to transport carbon monoxide produced by carbon dioxide electrolyzer 1313 to a carbon monoxide purification unit 1317. System 1301 may be configured to transport purified carbon monoxide from unit 1317 to a phosgene generation reactor 1319 configured to react the purified carbon monoxide with chlorine to produce phosgene. In certain embodiments, phosgene generation reactor 1319 is designed or configured to operate in a manner similar to other phosgene generation reactors described herein, such as in connection with a polycarbonate production system. Examples of carbon monoxide purification units are provided in Figures 19 and 20 and the associated description.

[0295] In certain embodiments, the carbon dioxide electrolyser located upstream from the phosgene generation reactor is adapted to operate in a carbon dioxide electrolyser that is operable to react with the phosgene generation reactor in a manner that utilizes (a) a high reduction product to hydrogen product stream operating parameter regime as described herein, and / or (b) a high reduction product to CO 2 It is configured to operate in a ratioed operating parameter regime.

[0296] In certain embodiments, the system 1301 includes an electrolysis cell, such as a chloralkali cell, for producing chlorine. The system 1301 may be configured to provide chlorine to the phosgene production reactor 1319. In some implementations, the system 1301 is configured to feed an oxygen by-product of the electrolyzer 1313 to a cathode of a chloralkali cell that includes an oxygen-depolarized cathode. Oxygen from the electrolyzer 1313 may be used in place of oxygen from other sources, such as air separation. In some implementations, the system 1301 includes a water electrolyzer, and the system 1301 is configured to feed oxygen produced by the water electrolyzer to the oxygen-depolarized cathode of the chloralkali cell. The system 1301 may be configured to provide hydrogen from the water electrolyzer to the amine production reactor.

[0297] In the embodiment shown, system 1301 is configured to transport phosgene from phosgene generation reactor 1319 to isocyanate generation reactor 1321, which is configured to react phosgene and an amine to produce a polyisocyanate, e.g., a diisocyanate such as toluene diisocyanate (TDI) or methylene diisocyanate (MDI), depending on the structure of the amine fed. In some implementations, reactor 1321 is configured to react phosgene and free amine in an inert organic solvent at low temperature. The resulting mixture of carbamoyl chloride and amine hydrochloride is then reacted at a higher temperature to produce the desired polyisocyanate.

[0298] In certain embodiments, the amine reactant is produced by a reactor or reaction utilizing one or more carbon oxide reduction products produced by a carbon oxide electrolyzer as described herein, for example, via Fischer-Tropsch and cracking reactions. In certain embodiments, the amine reactant is produced by a bioreactor, such as a gas fermentation reactor. In certain embodiments, the system 1301 is configured to provide hydrogen produced by electrolysis (optionally from the electrolyzer 1313 or water electrolyzer) to a gas fermentation reactor configured to produce an amine product or an intermediate used in amine production. In some implementations, hydrogen for amine production is provided by a separate source.

[0299] Regardless of the amine source, the reactor 1321 may be configured to react the polyamine with phosgene via a phosgenation reaction to produce a polyisocyanate, such as a diisocyanate. In certain embodiments, the diisocyanate is 2,4-toluene diisocyanate and / or 2,6-toluene diisocyanate. In certain embodiments, the diisocyanate is 4,4'-diphenylmethane diisocyanate.

[0300] In various embodiments, substantially pure carbon monoxide is used to produce phosgene, which is then reacted with various amines to produce isocyanates. Some amines may be produced using hydrogen, thus providing applications for by-product hydrogen from a carbon dioxide electrolyser or from a co-located water electrolyser.

[0301] As an example, for a system configured to produce toluene diisocyanate (TDI), the carbon dioxide electrolyzer may be configured or operated to produce a hydrogen-rich output stream. 2:CO ratios may be used to produce the precursors toluenediamine (TDA) and phosgene. TDA may be produced by hydrogenation of dinitrotoluene. For example, hydrogen may be used to produce nitric acid (described elsewhere), which is used for the nitration of toluene to produce dinitrotoluene.

[0302] In certain embodiments, a system including a carbon dioxide electrolyzer is configured to produce methylene diisocyanate (MDI) from aniline and phosgene. Aniline may be produced by hydrogenation of nitrobenzene. In some embodiments, a system for producing MDI via aniline is configured to produce a feed gas having a relatively high ratio of hydrogen to carbon monoxide (e.g., in the vicinity of about 3:1 hydrogen:CO). In some embodiments, the system is configured to produce nitric acid (described elsewhere), which is used for the nitration of benzene to produce nitrobenzene. The system may be configured to utilize a separate gas stream containing a relatively low concentration of hydrogen (e.g., in the vicinity of about 1:1 hydrogen and CO ratio), which may be used to produce formaldehyde, which in turn is reacted with aniline to produce diamines, which are then phosgenated to produce MDI.

[0303] In certain embodiments, a system including a carbon dioxide electrolyzer is configured to feed a hydrogen-rich gas stream (e.g., about 4:1 H 2 The system may be configured to produce hexamethylene diisocyanate (HDI) using a gas stream having a 1:1 ratio of adiponitrile to adiponitrile. The system may be configured to hydrogenate adiponitrile to produce hexamethylene diamine, which is then phosgenated to produce HDI. Polyurethane

[0304] 14 provides a schematic diagram of a system 1401 that may be utilized to produce polymer polyurethane. One group of reactors utilizes a carbon oxide electrolyzer 1403 configured to produce ethylene. Another group of reactors utilizes a carbon dioxide electrolyzer 1413 configured to produce carbon monoxide and hydrogen. In an alternative embodiment, only one of these two groups of reactors is utilized, and an alternative source is used to provide the intermediate chemicals that would otherwise be produced by the other of the groups of reactors.

[0305] In some implementations, system 1401 is configured to transport ethylene and optionally oxygen from electrolyzer 1403 to ethylene oxide production reactor 1405. System 1401 may be configured to provide ethylene oxide from reactor 1405 to ethylene glycol production reactor 1407 and / or polyethylene glycol production reactor 1409. In certain embodiments, ethylene oxide production reactor 1405 and / or ethylene glycol production reactor 1407 are designed or configured to operate in a manner similar to that of reactors 1005 and 1007 of system 1001.

[0306] The polyethylene glycol production reactor 1409 may be configured to produce polyethylene glycol from the interaction of ethylene oxide with water, ethylene glycol, and / or ethylene glycol oligomers. The PEG chain length and product polydispersity are affected by the selection and ratio of reactants. The system 1401 may be configured to transport heat generated by the exothermic PEG production reaction from the reactor 1409 to a carbon monoxide purification process (e.g., for phosgene production) or other energy demanding processes. Examples of carbon monoxide purification units are provided in Figures 19 and 20 and the associated description.

[0307] In some implementations, the system 1401 is configured to transport carbon monoxide and optionally hydrogen from the electrolyzer 1413 to a reactor or group of reactors 1415 configured to produce one or more polyols (e.g., polyethylene glycol). The reactor or group of reactors 1415 may be a bioreactor configured to produce polyols by a gas fermentation reaction. In some embodiments, the reactor 1415 is configured to produce polyols using an algae-based reaction. In certain embodiments, the reactor or group of reactors 1415 includes a Fischer-Tropsch reactor and / or a naphtha cracking reactor used to produce hydrocarbons that can be converted to polyols.

[0308] In certain embodiments, the carbon dioxide electrolyzer located upstream from the naphtha production and cracking subsystem is configured to operate in a hydrogen-rich product stream operating parameter regime as described herein, and / or a high reduction product vs. CO ratio as described herein. 2 It is configured to operate in a ratioed operating parameter regime.

[0309] The system 1401 may be configured to utilize the carbon monoxide and optionally hydrogen generated by the electrolyzer 1413 to generate a diisocyanate such as MDI or TDI. In a particular embodiment, the system 1401 is configured to implement diisocyanate generation using the system 1301 shown in FIG. 13 as a subsystem. Such a subsystem may include a carbon monoxide purification unit and a phosgene generation reactor. Regardless of how the diisocyanate precursors, such as phosgene and free amines, are generated, the system 1401 is configured to react them in the diisocyanate generation reactor 1421. Depending on the polyurethane to be generated, different types of diisocyanates may be utilized. Examples include 2,4-toluene diisocyanate and / or 2,6-toluene diisocyanate. In a particular embodiment, the diisocyanate is 4,4′-diphenylmethane diisocyanate.

[0310] System 1401 is optionally configured to provide excess carbon monoxide in the outlet stream of ethylene production electrolyzer 1403 to the phosgene / isocyanate production pathway.

[0311] System 1401 includes a polyurethane production reactor 1411 configured to receive a polyol and a diisocyanate and react them to produce a polyurethane polymer. In certain implementations, the polyol is produced, for example, by reactor or reactor group 1415 and / or polyethylene glycol production reactor 1409. In some implementations, system 1401 is configured to transport polyol from one or both of these reactors and / or transport diisocyanate from reactor 1421 to polyurethane production reactor 1411. In certain embodiments, reactor 1411 is designed or configured to contact and react vapors of polyol and diisocyanate. In certain embodiments, the polyol stream includes a catalyst (e.g., and acidic or basic amines), a surfactant, and / or a blowing agent. Oxalic acid

[0312] In certain embodiments, oxalic acid is produced from carbon monoxide produced by a carbon dioxide electrolyzer. A variety of pathways may be utilized to produce oxalic acid from carbon monoxide. Examples of systems incorporating these pathways are shown in Figures 15-18.

[0313] In certain embodiments, the carbon dioxide electrolyzer and associated oxalic acid production unit are deployed at or near a plant for producing cement. Carbon dioxide produced by the cement plant may be used as a feedstock for the carbon dioxide electrolyzer. Oxalic acid produced by the system may be used to harden the cement. In certain embodiments, the oxalic acid used in the cement produces calcium oxalate, which has very low solubility. Cement produced with oxalic acid may resist degradation due to contact with acid during use (e.g., after installation or construction).

[0314] 15 illustrates a system 1501 that includes a carbon dioxide electrolyzer 1503 configured to produce carbon monoxide and hydrogen. System 1501 is configured to transport a portion of the carbon monoxide and hydrogen produced by electrolyzer 1503, optionally along with some oxygen, to an alcohol production reactor 1505. Reactor 1505 is configured, in certain embodiments, to produce methanol or butanol.

[0315] In some implementations, the reactor 1505 is a bioreactor that utilizes an organism having a metabolic pathway for converting carbon monoxide to an alcohol, such as butanol. Examples of such organisms include autotrophic acetogens, such as Clostridium carboxydivorans and Butyrivacterium methylotrophicum. In some embodiments, the reactor 1505 is configured to produce methanol by catalytic reaction of carbon monoxide and hydrogen at elevated temperature and pressure. In some embodiments, the catalyst is a mixture of copper oxide and zinc oxide supported on alumina. In some embodiments, the system 1501 is configured to provide additional hydrogen to the alcohol reactor 1505 beyond the hydrogen produced by the electrolyzer 1503.

[0316] In certain embodiments, a carbon dioxide electrolyser located upstream from the alcohol production reactor is configured to operate in a hydrogen-rich product stream operating parameter regime as described herein, and / or a high reduction product vs. CO ratio as described herein. 2 It is configured to operate in a ratioed operating parameter regime.

[0317] System 1501 is further configured to transport the alcohol produced by reactor 1505 to oxalic acid production reactor 1507. In certain embodiments, reactor 1507 is configured to react the alcohol with carbon monoxide and oxygen to produce an oxalic acid diester, which is then hydrolyzed to produce free oxalic acid. 4ROH+4CO+O 2 →2(CO 2 R) 2 +2H 2 O

[0318] The carbon monoxide provided to the reactor 1507 may be provided directly from the electrolyzer 1503. In some embodiments, the carbon monoxide from the electrolyzer 1503 is purified prior to delivery to the reactor 1507.

[0319] Reactor 1507 may produce oxalic acid in an impure form. Thus, system 1501 may be further configured to provide the oxalic acid product to separator 1509, which may be configured to purify the oxalic acid and return unreacted alcohol to reactor 1507. In certain embodiments, separator 1509 is configured to perform azeotropic distillation on the oxalic acid product from reactor 1507.

[0320] Figure 16 illustrates a system 1601 configured to produce oxalic acid from carbon monoxide produced by an electrolyzer 1603. As shown, system 1601 is configured to transport carbon monoxide and hydrogen produced by electrolyzer 1603 to an ethylene glycol production reactor 1605. Reactor 1605 may be designed or configured to produce ethylene glycol similar to that described above with reference to system 1011 of Figure 10A (see reactor 1017).

[0321] In certain embodiments, a carbon dioxide electrolyser located upstream from the MEG production reactor is configured to operate in a hydrogen-rich product stream operating parameter regime as described herein, and / or a high reduction product vs. CO regime as described herein. 2 It is configured to operate in a ratioed operating parameter regime.

[0322] System 1601 is configured to transport ethylene glycol produced by reactor 1605 to oxalic acid production reactor 1607 configured to oxidize ethylene glycol to produce oxalic acid. In certain embodiments, reactor 1607 is configured to utilize an oxidant such as nitric acid and / or air to produce oxalic acid from ethylene glycol. In certain embodiments, reactor 1607 is configured to react alcohol (MEG) in the presence of an oxidant such as air or nitric acid using a catalyst such as vanadium pentoxide to produce oxalic acid.

[0323] In certain embodiments, the system 1601 includes a reactor 1609 for producing nitric acid. In certain embodiments, the reactor 1609 is designed or configured to implement an Ostwald process. In certain embodiments, the system 1601 additionally includes a reactor for implementing a Haber process to produce ammonia. The system 1601 may be configured to provide ammonia to the Ostwald reactor 1609. In some implementations, the Haber reactor and the Ostwald reactor 1609 are provided as subsystems that take hydrogen and nitrogen as reactants and produce nitric acid as a product. The system 1601 may be configured to direct hydrogen produced by the electrolyzer 1603 to a subsystem for producing nitric acid (e.g., a subsystem that first produces ammonia from hydrogen and nitrogen). In some embodiments, the nitric acid is provided from an external source. It should be understood that in other embodiments that require nitric acid, such as other systems for producing oxalic acid, the nitric acid can be produced from a Haber process subsystem that receives hydrogen from a carbon oxide electrolyzer.

[0324] In the embodiment shown, reactor 1607 receives nitric acid from reactor 1609 and produces oxalic acid. In certain embodiments, reactor 1609 produces relatively impure oxalic acid, such as oxalic acid containing some amount of nitric acid. In the embodiment shown, system 1601 is configured to deliver the impure oxalic acid to crystallizer and separator unit 1611, which is configured to purify the oxalic acid and return the nitric acid to reactor 1607.

[0325] FIG. 17A illustrates a system 1701 including a carbon dioxide electrolyzer 1703, a metal formate generation reactor 1705, and an oxalic acid formation reactor 1707. The system 1701 is configured to deliver carbon monoxide produced by the electrolyzer 1703 to the formate generation reactor 1705. In operation, metal hydroxide along with heat (optionally waste heat from the electrolyzer 1703) is provided to the metal formate generation reactor 1705. The production and purification and / or extraction of the formate may proceed as described above with reference to FIG. 9. In some implementations, the formate is an alkali metal formate, such as sodium, potassium, or cesium formate, or an alkaline earth formate, such as calcium or barium formate. In certain embodiments, the formate is sodium formate. In certain embodiments, the formate is potassium formate.

[0326] Regardless of how the metal formate is produced and optionally extracted, the system 1701 is configured to transport the formate to an oxalic acid production reactor 1707. The reactor 1707 may be configured to convert the formate to an oxalate via a pyrolysis reaction. The reactor 1707 may be configured to convert the metal oxalate to oxalic acid through contact with an acid. In certain embodiments, the oxalic acid formation reactor 1707 is configured to receive an acid, such as, for example, hydrochloric acid, to drive the reaction. In certain embodiments, the halide by-product (e.g., NaCl) of the oxalic acid production reaction (in the reactor 1707) is provided to a chloralkali electrolyzer or other system 1709 configured to produce chlorine gas and metal hydroxides. In some implementations, the system 1701 is configured to utilize chlorine to produce hydrogen chloride or hydrochloric acid, which may be delivered to the oxalic acid production reactor 1707. In some implementations, the system 1701 is configured to utilize hydroxide from reactor 1709 in the formate production reactor 1705.

[0327] As shown, oxalic acid may be produced from metal formates by conversion to metal oxalates and subsequent acidification. In some implementations, the process may include the following operations: (1) producing metal formates from carbon monoxide produced by a carbon dioxide electrolysis cell; (2) producing metal oxalates from metal formates, e.g., by pyrolysis; and (3) producing oxalic acid by exposing the metal oxalates to an acid. The entire process may be performed as a batch process. In some cases, at least the metal formate production operation and the metal oxalate production operation are performed in the same vessel. In some examples, the formate and / or oxalate production vessels may be pressure vessels, such as autoclaves. In some cases, the metal formate production vessels and / or metal oxalate production vessels include mechanisms for reducing the particle size of solid reactants, such as metal hydroxides. In some examples, the production vessels include ball mills.

[0328] In some embodiments, the formate-producing reaction (e.g., the reaction between carbon monoxide and solid sodium hydroxide), optionally during the reaction in an autoclave, has a residence time of at least about 15 minutes to 60 minutes, or about 20 minutes to 40 minutes. In some cases, the solid hydroxide is contacted with the carbon monoxide at a temperature of at least about 200° C. (e.g., about 230° C. to 300° C.) and / or at a pressure of at least about 2 bar (200 kPa) (e.g., about 5 bar (500 kPa) to 10 bar (1000 kPa)).

[0329] The act of converting the metal formate to metal oxalate may be accomplished by pyrolysis, optionally in the same reaction in which the metal formate was produced. This reaction may be carried out in the presence of heat and sodium carbonate. In a batch process in which a single reactor is used to produce the metal formate and metal oxalate, the metal carbonate (e.g., sodium carbonate) may be the only input added to the reactor prior to the oxalate reaction.

[0330] In some embodiments, the metal oxalate-forming reaction is carried out at a pressure of about 0.5 bar (50 kPa) to 5 bar (500 kPa) (e.g., substantially atmospheric pressure). In some embodiments, the metal oxalate-forming reaction is carried out at a temperature of at least about 200° C., or at least about 300° C., or at least about 300° C. to 400° C. In some embodiments, the residence time of the metal oxalate-forming reaction is about 10 minutes to 100 minutes, or about 20 minutes to 40 minutes.

[0331] In some implementations, at the start of the metal oxalate production reaction, the reactor pressure is reduced to a low pressure (e.g., about 1 bar (100 kPa)) while the reactor is heated until a temperature of at least about 300° C. (e.g., about 360° C.) is reached. During the pyrolysis operation, metal hydroxide residues may continue to react with carbon monoxide, which increases the overall conversion of the reaction.

[0332] The solid metal carbonate may act as a catalyst. Furthermore, it may inhibit the pyrolysis of metal oxalate to metal carbonate and carbon monoxide. In some implementations, the reactor pressure is reduced to low pressure (e.g., about 1 bar (100 kPa)) while the reactor is heated until a temperature of at least about 300° C. (e.g., about 360° C.) is reached. During the pyrolysis operation, the metal hydroxide residue may continue to react with carbon monoxide, which increases the overall conversion of the reaction.

[0333] In certain embodiments, the oxalic acid is formed from a metal oxalate and an acid, such as a hydrohalic acid. In certain embodiments, the acid is hydrochloric acid having a concentration of about 0.05M to 0.2M. In some implementations, the oxalic acid formation reaction is carried out in a crystallizer, such as a batch crystallizer. In some embodiments, the reactor is configured to generate a recycle stream to increase the efficiency of oxalic acid crystal separation.

[0334] In some embodiments, oxalic acid is generated at a temperature of about 20° C. to 100° C., or about 50° C. to 100° C. In some embodiments, the freshly generated oxalic acid is cooled (e.g., to about 30° C. or below) over a period of about 10 minutes to about 60 minutes. In some embodiments, the pressure utilized during the oxalic acid-forming reaction is about 0.5 bar (50 kPa) to 2 bar (200 kPa) (e.g., about atmospheric pressure). In certain embodiments, the reaction solution containing the metal oxalate is brought to a low pH, for example, about 1 to 3, or simply about 1.

[0335] In some implementations, the mass of water added to the metal oxalate is sufficient to complete dissolution of the metal oxalate at the initial temperature. The dissolution process may occur, for example, while the temperature in the batch is about 80° C. The crystallization process may occur when the temperature of the solution in the batch drops, for example, drops quickly. This operation may be made possible by using a bypass stream of the water that was initially used to dissolve the metal oxalate. That is, once the oxalic acid is completely dissolved, the water stream may flow directly to a heat exchanger located in the batch, avoiding the passage through the heater. The process for forming and crystallizing oxalic acid may be accomplished using a crystallizer, such as the crystallizer 1731 shown in FIG. 17B.

[0336] The crystallized oxalic acid is optionally filtered and / or dried. In some embodiments, the oxalic acid is filtered using a pusher centrifuge. In some embodiments, the oxalic acid is dried using a fluidized bed dryer. In some implementations, the filtered oxalic acid has a moisture content of about 20% to 30% by weight.

[0337] FIG. 17B illustrates a process 1720 for forming oxalic acid from a solid metal formate. As shown, process 1720 begins with the formation of a metal formate in operation 1721. The process involves the reaction of carbon monoxide from a carbon dioxide electrolyzer with the metal hydroxide. Any suitable process for making a metal formate may be utilized. Examples include any of the processes disclosed herein for producing a metal formate, including the process described in connection with FIG. 9. After the metal formate is produced, it is converted to a metal oxalate in operation 1723. In the operation shown, the formate to oxalate conversion reaction is carried out in the presence of a metal carbonate, such as sodium carbonate. In certain embodiments, one or both of operations 1721 and 1723 are carried out in a ball mill autoclave, such as autoclave 1729 shown in this figure.

[0338] After the metal oxalate is formed in operation 1723, the metal oxalate is reacted with an acid, such as a hydrohalic acid (e.g., hydrochloric acid), to form oxalic acid. See operation 1725. In some embodiments, this reaction may occur in a crystallizer, such as batch cooling crystallizer 1731 shown in this figure. The batch cooling crystallizer includes (1) an agitator, (2) a baffle, (3) a cooling jacket, (4) a jacket fluid inlet, (5) a jacket fluid outlet, and (6) an outlet valve. This arrangement promotes both the formation and crystallization of oxalic acid.

[0339] After the oxalic acid is formed and optionally crystallized in operation 1723, it is optionally purified and / or dried. In one example, purification is achieved by filtration. In one example, drying is achieved in a fluidized bed.

[0340] FIG. 18 illustrates a system 1801 including a carbon dioxide electrolyzer 1803 configured to produce carbon monoxide and hydrogen. The system 1801 is configured to provide the carbon monoxide and hydrogen produced by the electrolyzer 1803 to a Fischer-Tropsch reactor or gas fermentation reactor, both generally indicated by block 1805. Depending on the content of the products produced by the electrolyzer 1803 and the reactions taking place in the reactor 1805, additional hydrogen may be required to drive the reactions in the reactor 1805. To this end, the reactor 1805 may be configured with an inlet for externally generated hydrogen gas. The reactor 1805 is configured to produce naphtha, and the system 1801 is configured to convey the naphtha from the reactor 1805 to a naphtha cracking reactor 1807. The naphtha cracking reactor 1807 is configured to crack the naphtha in a manner that produces at least some propylene.

[0341] In certain embodiments, the carbon dioxide electrolyser located upstream from the propylene production reactor is adapted to operate in a hydrogen rich product stream operating parameter regime as described herein, and / or a high reduction product vs. CO ratio as described herein. 2 It is configured to operate in a ratioed operating parameter regime.

[0342] System 1801 is configured to deliver propylene to an oxalic acid production reactor 1809 configured to receive nitric acid and optionally oxygen in addition to propylene. In some implementations, system 1801 is configured to deliver excess oxygen from electrolyzer 1803 to reactor 1809. In certain embodiments, reactor 1809 is configured to absorb propylene into nitric acid and heat the resulting mixture while adding oxygen and removing nitrogen oxides. The resulting process produces oxalic acid, which system 1801 is configured to deliver to a separation unit, such as crystallizer and separator unit 1811. In certain embodiments, unit 1811 is configured to produce pure oxalic acid. System 1801 may be configured to return nitric acid from unit 1811 to reactor 1809.

[0343] In one version of system 1801, propylene is produced from carbon monoxide and hydrogen produced by the electrolyzer by a different route. In this version, system 1801 is configured to deliver carbon monoxide and hydrogen from carbon dioxide electrolyzer 1803 to an alcohol synthesis reactor 1813 configured to produce methanol or other alcohols. In certain embodiments, reactor 1813 is configured to receive additional hydrogen from a source separate from electrolyzer 1803. In some implementations, reactor 1813 is configured to produce alcohols in a manner similar to that of methanol synthesis reactor 1205 in FIG. 12.

[0344] The reactor 1801 is configured to transport alcohol produced by the alcohol synthesis reactor 1813 to a methanol-to-olefins reactor 1815 configured to convert the alcohol to one or more olefins, including propylene. The system 1801 is configured to transport propylene produced by the reactor 1815 to the oxalic acid synthesis reactor 1809. The methanol-to-olefins reactor 1815 may be configured to convert alcohol (e.g., methanol) to olefins by a reaction involving a network of chemical reactions in the presence of an acidic zeolite catalyst, such as H-SAPO-34. The temperature and other parameters of the reaction may be adjusted to produce a desired product, which in the system 1801 is propylene. In certain embodiments, the system 1801 is configured to operate the reactor 1815 at a temperature of about 600° C. to 650° C.

[0345] In various embodiments, a system utilizing a carbon dioxide electrolyzer to produce carbon monoxide and hydrogen is configured to produce methanol from the carbon monoxide and hydrogen by a method such as the methanol synthesis reactor 1205 in Figure 12. An associated system is configured to provide the resulting methanol to a formate synthesis reactor, which may be configured to run the BASF and / or Kemira-Leonard processes to produce methyl formate. Refining Unit

[0346] Various types of purification units may be utilized to purify or otherwise concentrate the carbon monoxide produced by the carbon dioxide electrolyzer. Examples include amine absorption units (e.g., approximately 20% by volume or less of CO 2 (used with gas streams having a concentration of CO 2 Utilizing the acidity of CO 2 CO / CO adsorption units, CO adsorption units (e.g., using copper compounds), molecular sieves, and metal-organic frameworks 2These include separation compositions, cryogenic systems (e.g., flash distillation systems), and membrane permeation units. In certain embodiments, the CO purification units are configured to operate at pressures between about 100 psia (689.476 kPaA) and 400 psia (2757.904 kPaA). 2 The absorbing unit may utilize an aqueous solution of an ethanolamine, such as methyldiethanolamine MDEA, optionally with piperazine to improve absorption kinetics. The amine absorbent may be regenerated by the application of heat. An exemplary unit utilizes an aqueous solution of about 30% (by weight) MDEA and 1% (by weight) piperazine.

[0347] Cryogenic systems work by cooling a gas mixture and then passing it through a fractionator to separate the gases by boiling point. Multiple fractionators may be used in a single process to separate and deliver purified components of a gas mixture.

[0348] Membrane purification processes use membranes that retain the desired product gas but are highly permeable to impurities in the gas stream. The membranes are packaged into modules where a high pressure gas mixture is input at an inlet. The membrane retains the desired product gas at high pressure and allows undesired impurity gases to remain in a separate low pressure stream. For CO purification, the membrane retains CO but is highly permeable to H 2 and CO 2 Pure CO will come out in the product stream. 2 , CO 2 , and a small volume of CO will remain in the waste stream. The low pressure waste stream can be repressurized by a compressor and passed through another membrane stage to increase the recovery of the CO product. Greater than 99% pure CO can result from the membrane-based separation process.

[0349] Adsorption processes for removing CO may be utilized. The adsorption process may utilize pressure swings, temperature swings, vacuum swings, or other changes in operating conditions (e.g., humidity swings). Adsorbents are typically solids or liquids that have a high affinity for the desired gas molecules under one extreme of operating conditions, and a low affinity for the gas molecules under the other extreme of operating conditions. For example, an adsorbent for CO under high pressure conditions (e.g., about 300 kPa, and about 40° C. to 60° C.) will remove CO. 2 and H 2 It is capable of capturing CO (about 60 mol%-70 mol%) from a mixture of CO and CO2. A system with four adsorption towers, each containing 8 L of adsorbent, results in a flow rate of about 5 Nm3-10 Nm3 of 99%-99.9% pure product CO. The use of larger towers or additional stages allows gas mixtures containing about 20%-30% CO to be upgraded to purity of about 99% or higher. Adsorbents for CO adsorption have been developed by Kobe Steel using copper dopants in solid matrices such as carbon, alumina, or silica.

[0350] 19 shows a system 1901 for demonstrating a carbon monoxide stream containing carbon dioxide and possibly other components such as hydrogen. As shown, system 1901 includes an absorber 1903 configured to selectively remove carbon dioxide by contacting a carbon dioxide-containing gas with an absorbent material such as ethanolamine. Absorber 1903 includes a gas inlet 1905 for receiving an inlet gas stream, such as a gas stream from a carbon dioxide electrolyzer (not shown). Absorber 1903 also includes a gas outlet 1907 for releasing purified carbon monoxide.

[0351] As also shown, absorber 1903 includes an inlet 1911 for receiving purified adsorbent and an outlet 1909 for discharging loaded adsorbent, e.g., adsorbent containing a higher concentration of carbon dioxide than the adsorbent entering absorber 1903.

[0352] The system 1901 also includes a regenerator 1913 configured to remove the carbon dioxide exhausted by the absorber 1903, thereby generating regenerated sorbent material for reuse in the absorber 1903. In the embodiment shown, the sorbent is regenerated by heating, which releases carbon dioxide. Heating is performed using a preheater 1915 and a reboiler 1917. In some embodiments, the reboiler 1917 is configured to receive waste heat from a carbon dioxide electrolyzer (not shown). The preheater 1915 is configured to receive the loaded sorbent from the outlet 1909 of the absorber 1903 and deliver the preheated sorbent to the inlet 1919 of the regenerator 1913. The preheater 1915 receives some heat from the lean sorbent on its way from the regenerator 1913 to the absorber 1903.

[0353] The system 1901 is configured to transport the lean sorbent from the outlet 1923 of the regenerator 1913 using a lean solvent pump 1921 to a preheater 1915 where the sorbent loses some of its heat. The system 1901 is also configured to transport the lean sorbent from the preheater 1915 to the absorber inlet 1911 via a trim cooler 1925. The trim cooler 1925 cools the sorbent to the CO 2 in the absorber 1903. 2 The trim cooler is configured to further cool the trim to a temperature where it can effectively perform its job of removing the impurities. The trim cooler may be a water cooled module.

[0354] As shown, the reboiler 1917 is configured to provide heat for the regenerator 1913 to release carbon dioxide from the charged sorbent. As shown, the reboiler 1917 is included in a recirculation loop that receives a portion of the lean sorbent from the regenerator outlet 1923 and returns the heated lean sorbent to the regenerator 1913 via inlet 1927.

[0355] In addition, the system 1901 includes a recycle compressor 1931 configured to compress the carbon dioxide, for example, to a pressure suitable for entering the carbon dioxide electrolyzer that produces an inlet carbon monoxide-containing stream.

[0356] System 1901 also includes a subsystem associated with the regenerator 1913 that utilizes a condenser 1933 to condense a portion of the sorbent that may be included in the released carbon dioxide that exits the regenerator 1913 through a gas outlet 1935. Note that the condenser 1933 is configured to condense the sorbent and deliver it back to the regenerator 1913 at a sorbent inlet 1937.

[0357] In some cases, the CO purifier is a hybrid system having two different purification subsystems connected in series. For example, the CO purifier may have a cryogenic subsystem upstream from the adsorbent subsystem. Hybrid systems may be used in systems where the input CO stream has a relatively low concentration of carbon monoxide, such as less than about 70% molar.

[0358] 20 shows a hybrid carbon monoxide purification system 2001 having a cryogenic pre-treatment subsystem 2003 and a sorbent post-treatment subsystem 2005. The first phase of system 2001 is the cryogenic subsystem 2003, which is configured to partially concentrate carbon monoxide. In certain embodiments, the cryogenic subsystem is configured to concentrate carbon monoxide to a level of at least about 70% by volume.

[0359] As shown, the cryogenic pre-treatment subsystem 2003 is configured to feed product gas, for example from a carbon dioxide electrolyzer (not shown), to a compressor 2007 configured to compress the gas to a prescribed pressure or density. The system 2001 is configured to transport the compressed gas from the compressor 2007 to a chiller 2011 configured to reduce the temperature of the compressed gas. The chiller 2011 is coupled to a refrigeration system 2009 configured to remove sufficient heat from the chiller 2011 to maintain the compressed gas at or below a desired temperature.

[0360] The chiller 2011 is configured to chill the compressed gas to a reduced temperature. The chiller 2011 is configured to cool the compressed gas to a reduced temperature. 2 Receives the slurry (provided with a reduced temperature) and CO 2 to a trim vaporizer 2013 configured to release vaporized carbon dioxide. The vaporized carbon dioxide from the trim vaporizer 2013 may be transported by the system 2001 to a recycle compressor 2015 configured to provide pressurized carbon dioxide suitable for feeding to the cathode side of a carbon dioxide electrolyzer.

[0361] In the embodiment shown, the cryogenic subsystem 2003 is configured to provide the chilled, compressed output of the chiller 2011 to a Joule Thompson valve 2017 that is configured to rapidly expand the compressed gas, thereby further cooling the gas. This action causes the gaseous CO 2 The gas may be cooled sufficiently to convert a portion of the carbon dioxide to a liquid or solid or slurry. The cooled gas is nevertheless provided to a separator 2019 connected to a Joule Thompson valve 2017 and having a carbon dioxide slurry outlet 2021 and a partially purified carbon monoxide gas stream outlet 2023. In certain embodiments, the partially purified carbon monoxide stream has a concentration of at least about 50% Molar or at least about 70% Molar.

[0362] In the embodiment shown, system 2001 is configured to provide the partially purified carbon monoxide gas stream from outlet 2023 to an adsorbent post-treatment subsystem 2005, which in the embodiment shown is configured similarly to the overall adsorbent system 1901. As shown, subsystem 2005 has an absorber 2033 configured to absorb carbon dioxide from the partially purified CO stream and output purified CO gas. Subsystem 2005 also has an adsorbent regenerator 2043. Other components of subsystem 2005 include an adsorbent trim chiller, an adsorbent preheater, a lean sorbent pump, an adsorbent reboiler, and an adsorbent condenser. In some embodiments, the reboiler is configured to receive waste heat from a carbon dioxide electrolyzer (not shown).

[0363] Although the discussion of Figures 19 and 20, as well as other discussions of carbon monoxide purifiers, describe the case with carbon dioxide removal, the carbon monoxide purifier may additionally or alternatively be configured to remove other impurity gases, such as sulfur-containing gases (e.g., sulfur oxides). Auxiliary Hydrogen Source

[0364] In certain embodiments, an integrated system utilizing a carbon oxide electrolyzer includes an additional hydrogen source (beyond that produced from the electrolyzer) or is configured to receive additional hydrogen from an external source. Examples of integrated systems that may utilize an additional hydrogen source include Fischer-Tropsch systems, polycarbonate production systems, ethylene glycol production systems, polyethylene terephthalate production systems, methanol, butanol, and / or other alcohol production systems, acetic acid production systems, isocyanate production systems, polyurethane production systems, and oxalic acid production systems. In certain embodiments, the additional hydrogen source is a water electrolyzer, such as a proton exchange membrane water electrolyzer. In some implementations, the water electrolyzer shares an electrical infrastructure with the carbon oxide reduction electrolyzer. In certain embodiments, the additional hydrogen source is a tank, canister, or other storage tank external to the integrated system. In certain embodiments, the additional hydrogen source is or includes units configured to perform: (a) steam reforming, thermal cracking, and / or partial oxidation of methane, fuel oil, petroleum coke, and / or other fossil fuels, coal gasification, (b) steam methane reforming, (c) gasification, pyrolysis, and / or other high temperature conversion of biomass, municipal solid waste, and / or other waste sources, (d) pressure swing adsorption of refinery waste streams, (e) separation of hydrogen by-product from industrial reactions such as molten chloride salt production, and / or (f) dissociation of water, for example, by solar / thermal energy. In certain embodiments, the methane or other simple hydrocarbons used in one or more of these units are obtained from biogas. Carbon dioxide capture from electrolyser output

[0365] In many implementations, the product gas leaving the cathode of the carbon dioxide electrolyzer contains a significant proportion of unreacted carbon dioxide. For example, the product gas may contain between about 10% molar and 70% molar carbon dioxide. In certain embodiments, the system includes a carbon dioxide capture unit arranged to receive the product gas from the carbon dioxide electrolyzer and generate a concentrated carbon dioxide product, which may optionally be recycled to the electrolyzer. In one example, the carbon dioxide capture unit comprises a direct air carbon dioxide capture module as described elsewhere herein. It should be understood that the product gas from the carbon dioxide electrolyzer may contain a much higher concentration of carbon dioxide than air. Thus, the direct air capture unit used with the electrolyzer may have a modified configuration compared to the corresponding unit used for direct air capture. By way of example, the direct air capture unit may utilize temperature swing absorption, pressure swing absorption, or electron swing absorption.

[0366] FIG. 21A illustrates an upstream DAC unit 2105 configured to concentrate carbon dioxide from air, and extract unreacted CO from the product gas of the carbon dioxide electrolyzer 2103. 2 2 shows system 2101 with a downstream DAC unit 2107 configured to remove purified unreacted carbon dioxide. System 2101 is configured to combine the purified unreacted carbon dioxide with fresh carbon dioxide from the upstream DAC unit 2105 and introduce it to the electrolyzer 2103. The downstream DAC unit 2107 may be designed differently (e.g., amount of solvent, contactor dimensions) than the upstream DAC unit 2105 to handle significantly different concentrations of carbon dioxide in the air versus the product gas.

[0367] Figure 21B shows a system 2111 having a DAC unit 2115 configured to capture carbon dioxide from air and separate unreacted carbon dioxide from the product gas of the electrolyzer 2113. The system 2111 is configured to feed the separated carbon dioxide to the electrolyzer 2113. The carbon dioxide-lean product and carbon dioxide-lean air leave the DAC unit 2115 for downstream processing. Integration with the Electric Grid

[0368] Various problems can arise when the electrical energy sources for the grid are not directly controllable in response to demand. Solar, wind, and certain other non-combustion based electrical energy sources are examples of sources where energy generation is decoupled from energy demand.

[0369] When renewable energy sources are connected to an electrical grid, fluctuations in wind speed or sunlight intensity can reduce the amount of power available on the grid to the point where demand exceeds supply, which can cause the frequency of the grid to drop, which can damage some electrical equipment and / or cause brownouts or blackouts.

[0370] To prevent this, flexible generators and consumers may be used in conjunction with renewable power sources. Such components may facilitate an electric grid load leveling system and may be configured to draw flexible loads from the grid, reducing power demand when necessary to prevent demand from approaching supply. This may provide frequency stabilization to the grid, enabling it to operate with large amounts of renewable electricity.

[0371] Various approaches have been proposed to store the excess energy generated when supply exceeds demand. Examples include water reservoirs, batteries, and water electrolysers. As an example, using batteries to store excess energy on the grid requires a large number of high capacity batteries to provide sufficient capacity to store the maximum excess energy that the energy sources on the grid can generate.

[0372] In comparison, carbon oxide electrolysers may store excess energy in liquid or gas form, which is relatively easy to store, and in comparison to water electrolysers, carbon oxide reduction cells may operate in a manner that produces a liquid product rather than a gaseous product, which may be easier to store, especially given its relatively high density.

[0373] The products of the carbon oxide electrolyzer can be used as fuel to generate electrical energy to put on the grid in periods when demand may exceed supply. The electrolyzer products may be combusted in a turbine or other mechanical power source and / or consumed electrochemically in a fuel cell to directly generate electrical power. In certain embodiments, the carbon oxide electrolyzer output, such as carbon monoxide or methanol, is stored in a fuel cell for later use to directly inject electrical energy back into the grid. In certain embodiments, the fuel cell is a fuel cell configured to oxidize a carbon-containing reactant (e.g., natural gas), such as a solid oxide fuel cell from Bloom Energy of Sunnyvale, CA.

[0374] CO 2 The electrolysis products can be gas (e.g., CO, methane, ethylene) or liquid phase (e.g., ethanol, methanol, ethylene glycol). Liquid products have the advantage of being easily stored for long periods of time. Gas phase products can be converted to liquid phase chemical compounds through a wide range of downstream processes, such as gas fermentation or thermochemical reactions. Gas and liquid phase products can also be used to create solid materials. For example, CO is one of the inputs required to create polycarbonate, or can be reacted with potassium hydroxide to create potassium formate.

[0375] 22A shows a system 2201 that couples a carbon oxide reduction electrolyzer 2203 to an electrical grid 2205 or other source of electrical energy. The system 2201 may be configured to operate in a manner that stores excess energy generated by the electrical system when the energy being generated exceeds the demand for electrical energy.

[0376] In system 2201, a variable electrical energy source 2206 generates electrical energy that is optionally provided to an electrical grid 2205. In the embodiment shown, the energy source 2206 is coupled to the grid 2205 via an electrical line having a rectifier 2207 and a transformer 2209. These and / or other electrical components may be utilized to provide the electrical energy from the variable source 2206 to the grid 2205 at an appropriate voltage and waveform.

[0377] In the embodiment shown, grid 2205 is connected to a demand for electrical energy that is approximately constant at least compared to the variability of electrical energy supply 2206. In the embodiment shown, the demand is represented by element 2208, which generally represents one or more electrical energy consumers, such as residential and / or industrial consumers. For many applications, the energy consumers require electrical energy at a voltage and electrical waveform that can be generated by rectifier 2211 and transformer 2213. As shown, these elements are provided between grid 2205 and demand 2208.

[0378] As shown, the illustrated embodiment provides an electrolytic carbon oxide reduction cell or stack 2203 that is configured to consume excess electrical energy from a grid or other electrical energy system by converting the excess energy into chemical products of electrolytic carbon oxide reduction. If this cell or stack 2203 receives electrical energy directly from the grid, it may require the electrical energy to be rectified and transformed, such as by a rectifier 2217, a transformer 2219, and / or other electrical components.

[0379] The cathode side of the electrolyzer 2203 receives carbon oxide reactants (carbon dioxide and / or carbon monoxide) via an inlet line. The carbon oxide may be provided by any one or more of many possible sources or raw materials 2222, such as those described elsewhere herein.

[0380] The cathode is configured to produce products such as gaseous or liquid C1 compounds (e.g., carbon monoxide, methane, formaldehyde, or formic acid) or gaseous or liquid higher carbon compounds such as ethylene. Such products along with other components are removed from the electrolyzer 2203 via an outlet line. In certain embodiments, the outlet gas, which may be humidified, is provided to a gas separator 2225, which condenses water and / or one or more liquid products. Unreacted carbon oxides and / or water may be provided back to the carbon oxide electrolyzer 2203 via line 2221. In certain embodiments, the carbon oxides provided to the electrolyzer are humidified to facilitate the reduction reaction.

[0381] In the embodiment shown, various optional components are provided downstream from the cathode side of the electrolyzer 2203. These include a demister 2227, a mass flow meter or controller 2229, a condensation trap 2231, a valve 2233, a gas reservoir 2235, a purification module 2237, and a product conversion system / reactor 2239. The resulting fuel, chemical, or other material 2241 is stored or used as appropriate. As mentioned, the chemical products of the electrolyzer 2203 store excess energy generated by the variable energy source. That energy may be recovered by converting the chemical energy stored in the products to heat or electrical energy by combustion, fuel cell operation, etc. Alternatively, the energy is not recovered, at least not in the short term, and the electrochemical reduction products are converted to another useful commodity, such as plastics.

[0382] The electrolyzer 2203 also includes an anode that receives an anode reactant, such as water, that is electro-oxidized at the anode. In the embodiment shown, a water source 2243 is provided to the anode of the cell 2203 via one or more optional components, such as a feed water pump 2245, a demister 2247, a gas separation unit 2249 (which also has an inlet for receiving products from the anode, which may include water vapor and oxygen), a circulation pump 2251, a mass flow meter or controller, and an ion exchanger configured to remove ions or other components of the anode water that may be harmful to the operation of the electrolyzer 2203. In certain embodiments, the system 2201 includes a line connecting the anode water recirculation loop to a carbon oxide inlet line 2221 to humidify the carbon oxide delivered to the cathode side of the electrolyzer 2203.

[0383] System 2201 may also include one or more components for removing oxygen or other products of electrolyzer 2203. The anode side of electrolyzer 2203 includes an outlet line 22057 configured to remove oxygen or other products from the electrolyzer. Outlet line 2207 connects to a separation unit 2249. Oxygen and water in the anode product stream may be separated from one another in unit 2249 such that the water can be recycled back to the anode via circulation pump 2251.

[0384] System 2201 may be configured with components for removing oxygen or other gaseous products of the anode. In the embodiment shown, these components are a demister 2259 and a control valve 2261.

[0385] In these examples, and throughout this disclosure, the systems described may be provided in a facility, plant, or building complex. In some embodiments, all or many of the reactors and units and / or modules of the system are provided in a common factory, plant, or complex. For example, a system for producing a particular material, such as polycarbonate polymer or transportation fuel, may include a carbon oxide electrolyzer and one or more other reactors that utilize the products of the electrolyzer and / or provide reactants to the electrolyzer, with the electrolyzer and the other reactors being provided in a single building or plant. In some cases, one or more system components are provided in an external environment. For example, the system may be configured to provide carbon dioxide from a direct air capture unit to the electrolyzer, but the direct air capture unit may be provided externally, while the carbon dioxide electrolyzer is located inside the building.

[0386] Further examples of grid management systems utilizing electrolyzers are shown in Figures 22B and 22C. As shown, systems 2258 and 2259 utilize a fuel cell configured to oxidize a carbon-containing reactant (e.g., methane or natural gas), such as a solid oxide fuel cell from Bloom Energy as mentioned above. In the embodiment shown, carbon oxide electrolyzer 2261 is coupled to a grid or other electrical energy source 2263, such as a device configured to generate electricity from wind, solar, or other renewable energy sources. In addition to electrical energy, electrolyzer 2261 receives carbon dioxide and water as inputs. In certain embodiments, carbon dioxide input is received, at least in part, from the output of fuel cell 2265. A compressor 2267 may be provided to compress such carbon dioxide prior to delivery to electrolyzer 2261.

[0387] 22B , electrolyzer 2261 is configured to output carbon monoxide, and system 2258 is configured to deliver the carbon monoxide to fuel cell 2265. System 2258 may be further configured to provide natural gas or other input to fuel cell 2265, which in turn is configured to generate electricity that can be provided to grid 2263. In some implementations, system 2258 includes a steam methane reformer unit 2271 configured to generate hydrogen for input to fuel cell 2265.

[0388] As shown in the embodiment of Figure 22C, electrolyzer 2261 is configured to output any one or more of a variety of compounds including carbon monoxide, ethylene, methane, etc. In certain embodiments, one or more of these compounds are removed from system 2259, potentially for purposes unrelated to electrical load leveling. For example, one or more of the compounds may be used as a feedstock for synthesizing compounds or polymers as described elsewhere herein.

[0389] In the embodiment shown, the system 2259 is configured to deliver at least a portion of the output of the electrolyzer 2261 to the fuel cell 2265, optionally along with natural gas or other fuel from an external source. In certain embodiments, the output from the electrolyzer 2261 is provided as synthetic natural gas or converted to form such gas. The system 2259 is configured to provide synthetic natural gas, alone or along with other natural gases, to the fuel cell 2265. In certain embodiments, the system 2259 is configured to provide carbon monoxide and / or other output of the electrolyzer 2261 directly to the fuel cell 2265. In some implementations, the system 2259 includes a steam methane reformer and / or a pressure swing absorption unit 2273 or other purification unit configured to process the gas before it is input to the fuel cell 2265. The steam methane reformer may convert methane from the natural gas source and / or the electrolyzer into hydrogen for delivery to the fuel cell 2265. A pressure swing absorption unit may be used to remove some of the carbon dioxide or other impurities from the inlet stream to the fuel cell 2265. In some embodiments, another type of impurity removal unit is utilized.

[0390] In certain embodiments, such as those shown in Figures 22B and / or 22C, a pressure swing absorber or other gas purification unit is configured to separate a pure hydrogen stream from the gas mixture exiting the steam methane reformer. The tail gas from the reformer is enriched with CO, CO 2 , unreacted CH4, and some H 2 The tail gas may be fed to a fuel cell, which in turn may contain relatively pure CO 2 (and water), which is then 2The steam methane reformer is configured to create a product with a relatively high concentration of hydrogen by utilizing a water-gas shift reaction after the reforming reaction. The water-gas shift reaction converts carbon monoxide and water (reactants) into carbon dioxide and hydrogen. In some implementations, the steam methane reformer is configured to create a synthesis gas mixture and may not implement a water-gas shift stage.

[0391] In some implementations, such as those shown in FIG. 22B and / or FIG. 22C, the steam methane reformer comprises two CO 2 Contains streams: (1) tail gas coming from the reactor, as explained above, and (2) flue gas coming from the furnace, which is used to heat the reactor tubes and generate steam for the reaction. The tail gas may contain a fairly high concentration of carbon dioxide (e.g., about 15% before separation and then about 50% after separation). The flue gas contains a relatively low concentration of carbon dioxide (e.g., only about 3%-5% CO 2 In various implementations, about two-thirds of the carbon dioxide emissions are from the tail gas and about one-third are from the flue gas. In certain embodiments, the system is configured to capture emissions from (a) the tail gas before purification (e.g., using a pressure swing absorber), (b) the tail gas after purification, (c) the flue gas, or (d) a combined stream from the flue gas and the tail gas. In some implementations, the system is configured to feed oxygen from the carbon oxide electrolyzer to one or more furnaces of the steam methane reformer. In some implementations, this provides higher efficiency and / or results in higher carbon dioxide concentrations in the flue gas, thereby simplifying carbon dioxide capture.

[0392] The fuel cell 2265 is configured to output electricity that can be delivered to the grid 2263. In certain embodiments, the system 2259 includes a carbon dioxide storage unit 2269 configured to store the carbon dioxide output from the fuel cell 2265 prior to use by the electrolyzer 2261. Syngas Preparation

[0393] The embodiments described in this section and / or illustrated in Figures 23A-23D relate to creating mixtures of carbon monoxide and hydrogen. Some of these mixtures may be referred to as synthesis gas. The embodiments described herein relate to methods and systems configured to receive a mixture of carbon monoxide, carbon dioxide, and hydrogen and modify the mixture to produce a mixture of carbon monoxide and hydrogen having a particular composition. In some cases, the input is a gas mixture obtained from a carbon oxide electrolyzer, such as one of the carbon oxide electrolyzers described herein.

[0394] The carbon monoxide and hydrogen mixture produced as described herein may have a variety of applications. It can be used to produce naphtha or other liquid hydrocarbon compositions such as may be produced by the Fischer-Tropsch process (see, e.g., the discussion of Figures 6A and 6B). It can also be used as input to a gas fermentation reactor (see, e.g., Figures 4 and 5). It can also be used to produce any of a variety of chemicals, such as alcohols (see, e.g., Figures 15 and 18) and / or polyols (see, e.g., Figures 14 and 16).

[0395] Various embodiments for producing a mixture of carbon monoxide and hydrogen may utilize a carbon oxides separator system such as those described in connection with FIGS.

[0396] The mixture of carbon monoxide and hydrogen is separated from the input stream by CO or CO 2 In embodiments where the mixture is produced by directly separating CO from an input stream, hydrogen may be added to a purified CO stream downstream from a CO purification operation. For example, purified hydrogen may be added to a CO stream downstream from a CO separation operation by directly removing CO from the input stream. 2 It may be prepared by separating it from

[0397] FIG. 23A shows an overall scheme for producing a mixture of carbon monoxide and hydrogen in a process for separating carbon monoxide directly from an input stream. The input stream, which may be provided from the cathode outlet of a carbon dioxide electrolyzer, contains carbon dioxide, carbon monoxide, hydrogen, and optionally small amounts of other components such as water and / or hydrocarbons. The input stream is fed to one or more separation elements 2303 configured to produce one stream 2305 containing purified carbon monoxide and another stream 2307 containing a mixture of carbon dioxide and hydrogen. Element 2303 may include, for example, a CO2 absorption element and / or a CO2 absorption and stripping subsystem, for example a pressure swing or temperature swing subsystem. Steam 2307 is fed to one or more elements 2309 configured to separate hydrogen from carbon dioxide. In some embodiments, element 2309 includes, for example, a membrane separator that blocks the passage of carbon dioxide while allowing the passage of hydrogen. In operation, element 2309 produces a hydrogen stream 2311 and a carbon dioxide stream 2313. Hydrogen stream 2311 may be combined with carbon monoxide stream 2305 to produce stream 2315 containing a mixture of carbon monoxide and hydrogen. Carbon dioxide stream 2313 may optionally be recycled to the carbon oxide electrolyzer.

[0398] In some embodiments, the process of making a mixture of hydrogen and carbon monoxide may be characterized by the following operations: 1. Separation of CO from mixtures by ionic liquid absorption, e.g. in pressure swing absorption processes 2. CO through a membrane, for example 2 From H 2 Separate 3.H 2 and CO

[0399] In certain embodiments for producing purified carbon monoxide directly from an input stream, an ionic liquid is used to strip carbon monoxide from the input gas stream. During separation, the ionic liquid contacts the input gas and selectively absorbs the carbon monoxide while allowing most of the hydrogen and carbon dioxide to pass through (undissolved or unabsorbed). In some embodiments, the input stream is contacted with the ionic liquid in an absorption column. After contact, the input stream, a carbon monoxide-rich stream of ionic liquid, is fed to a stripper operating under conditions to strip carbon monoxide from the ionic liquid. The resulting lean stream of ionic liquid may be recycled back to the component that selectively absorbs carbon monoxide.

[0400] Suitable ionic liquids for carbon monoxide separation preferentially absorb carbon monoxide without substantially absorbing carbon dioxide and / or hydrogen. Other properties may include low cost, low vapor pressure (e.g., no generation of volatile organic compounds during use), low kinetic viscosity (e.g., less than about 150 cSt), moderate absorption conditions (e.g., temperatures between about 0° C. and 20° C.; pressures of about 25 bar (2500 kPa) or less (e.g., about 17 bar (1700 kPa))), moderate stripping conditions (e.g., temperatures between about 0° C. and 100° C.; pressures of about 5 bar (500 kPa) or less), and / or low toxicity. Examples of such ionic liquids include 1-hexyl-3-methylimidazolium chloride (with cuprous chloride).

[0401] In some embodiments, the mixture of carbon monoxide and hydrogen is produced by directly removing carbon dioxide from an input stream containing carbon monoxide, hydrogen, and carbon dioxide. In such embodiments, one output stream of the separation contains the desired mixture of hydrogen and carbon monoxide.

[0402] FIG. 23B shows an overall scheme for producing a mixture of carbon monoxide and hydrogen in a process for separating carbon dioxide directly from an input stream. The input stream, which may be provided from the cathode outlet of a carbon dioxide electrolyzer, contains carbon dioxide, carbon monoxide, hydrogen, and optionally small amounts of other components such as water and / or hydrocarbons. The input stream is fed to one or more elements 2302 configured to produce a carbon dioxide stream 2304 containing purified carbon dioxide and another stream 2306 containing a mixture of carbon monoxide and hydrogen. Element 2302 may include, for example, a subsystem including a carbon dioxide absorption element or a carbon dioxide absorption and stripping element, for example a pressure swing or temperature swing subsystem. The carbon dioxide stream may optionally be recycled to the carbon oxide electrolyzer.

[0403] In certain embodiments for removing carbon dioxide directly from an input stream, an ionic liquid is used to strip carbon dioxide from an input gas stream. The ionic liquid contacts the input gas and selectively absorbs the carbon dioxide while allowing most of the hydrogen and carbon monoxide to pass through. In some embodiments, the input stream is contacted with the ionic liquid in an absorption column. After contact, the input stream, a carbon dioxide-rich stream of ionic liquid, is fed to a stripper operating under conditions to strip the carbon dioxide from the ionic liquid. The resulting lean stream of ionic liquid may be recycled back to the component that selectively absorbs carbon dioxide.

[0404] Suitable ionic liquids for separating carbon dioxide preferentially absorb carbon dioxide without substantially absorbing carbon monoxide and / or hydrogen. Other properties may include low cost, low vapor pressure (e.g., no generation of volatile organic compounds during use), low kinetic viscosity (e.g., less than about 150 cSt), moderate absorption conditions (e.g., temperatures of about 15° C. or higher; pressures of about 50 bar (5000 kPa) or lower), moderate stripping conditions (e.g., temperatures of about 0° C. to about 100° C. or lower; pressures of about 5 bar (500 kPa) or lower), and / or low toxicity. Examples of such ionic liquids include 1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF6].

[0405] In some implementations, a system configured to produce a mixture of carbon monoxide and hydrogen does not include a component configured to cool an inlet or outstream to less than about 30° C., or less than about 20° C., or less than about 10° C. For example, the system does not include a compressor to cool the inlet gas to less than about 20° C. CO separation example

[0406] As described, carbon monoxide and hydrogen are included in the output from the carbon dioxide electrolyzer. This electrolyzer output gas serves as the input to a separation system that produces a mixture of carbon monoxide and hydrogen. In some embodiments, carbon monoxide is recovered from the gas stream by a pressure swing absorption process using an ionic liquid such as 1-hexyl-3-methylimidazolium chloride (CuCl).

[0407] The pressurized inlet gas stream enters at the bottom of the absorption column while the absorbent is sprayed from the top of the column. The packed bed may improve contact between the gas and liquid phases and facilitate carbon monoxide absorption. 2 , H 2 , and a small amount of residual CO) leaves the top of the column, while a CO2-rich liquid phase leaves the bottom of the column.

[0408] In certain embodiments, the absorbent material comprises a mixture of CuCl and an ionic liquid (e.g., about 50% molar CuCl and 50% molar ionic liquid 1-hexyl-3-methylimidazolium chloride). The inlet molar amount of CuCl can be about 1.5 to 2.5 times (e.g., about 1.9 times) greater than the amount of carbon monoxide to be absorbed.

[0409] The CO2-rich liquid phase is heated in a heat exchanger and then enters the stripping column. The pressure in the stripping column may be less than 2 bar (200 kPa) (e.g., about atmospheric), while the temperature may be relatively low at the top (e.g., about 30° C.) and relatively high at the bottom (e.g., about 60° C.). Under these conditions, most of the CO2 may evaporate. The liquid phase flows to the bottom of the column, where some proportion (e.g., about 15%) is recycled back to the column, for example using a full reboiler, while the remainder (e.g., about 85%) flows back to the absorption column. In certain embodiments, the boiled liquid coming from the reboiler transfers heat to the incoming stream. In some embodiments, the reboiler is configured to receive waste heat from the carbon dioxide electrolyzer.

[0410] See the following CO2 absorption stripping components of system 2321 shown in FIG. 23C: Inlet stream 2322 is compressed and cooled by compressor 2323 working in conjunction with chiller 2324. The compressed and cooled inlet gas enters the bottom of absorption column 2325 where the CO2 in the inlet stream is selectively absorbed by a liquid. The CO2-rich liquid phase is heated in heat exchanger 2326 (stream 5) and then enters stripping column 2327 (stream 6). The pressure in the stripping column may be atmospheric, while the temperature may range, for example, from 30° C. at the top to 60° C. at the bottom. The solubility of CO2 in the absorbent at these operating parameters is low and most of the CO2 is evaporated. The liquid phase flows to the bottom of column 2327 (stream 8) where approximately, for example, 15% is recycled back to column 2327 using reboiler 2328 (streams 9 / 10), while the remaining, for example, 85% flows back to absorption column 2325 (streams 11-16).

[0411] CO 2 and H 2 A gas stream of CO exits the top of the absorption column 2325. 2 and H 2 may be separated by a variety of techniques. In some embodiments, they are separated using a membrane filter 2330. In some embodiments, the membrane filter is a Polaris™ filter from Membrane Technology and Research Corporation Inc., Newark, Calif. Such membranes are 2 Compared to CO 2 , which is taken as the retentate. In some examples, the membrane filter operates at a pressure of about 5 bar (500 kPa) to 15 bar (1500 kPa) (e.g., about 9 bar (900 kPa) pressure) and / or at a temperature of about 0° C. to 20° C. (e.g., about 5° C.). CO 2 Separation Example

[0412] Similar to the CO absorption embodiment, carbon monoxide and hydrogen are included in the output from the carbon dioxide electrolyzer. This electrolyzer output gas serves as the input to a separation system that produces a mixture of carbon monoxide and hydrogen. In certain implementations, the CO 2 is absorbed directly from the input stream using an ionic liquid such as [bmim][PF6]. Absorption may occur at any of a variety of pressures (e.g., from about 10 bar (1000 kPa) to 60 bar (6000 kPa)). In some implementations, the pressure of the inlet gas stream may be from about 8 bar (800 kPa) to 16 bar (1600 kPa). To this end, the system may utilize additional compression with a compressor.

[0413] In some embodiments, CO 2 The absorption column operates at a relatively high pressure, such as about 20 bar (2000 kPa) to 60 bar (6000 kPa) or about 40 bar (4000 kPa) to 50 bar (5000 kPa) (e.g., about 44 bar (4400 kPa)). At this pressure and 25° C., 2 The solubility of CO in 1 mole of ionic liquid is about 0.2 moles. 2 The absorption column operates at a relatively low pressure, such as from about 1 bar (100 kPa) to 20 bar (2000 kPa). In certain embodiments, the absorption column operates at a temperature of from about 20°C to 80°C, or from about 20°C to 30°C, or from about 40°C to 60°C.

[0414] FIG. 23D illustrates an exemplary CO electrolysis system for processing the output of a carbon oxide electrolyzer to produce a mixture of carbon monoxide and hydrogen. 2 Shown is an absorption stripping system 2351. The inlet stream is compressed by compressor 2353. The compressed inlet gas (stream (2)) enters the bottom of the absorption column 2355, where the CO 2is selectively absorbed by a liquid (e.g., an ionic liquid). The flow rate of the absorbent liquid may be adjusted or controlled by monitoring the molar flow rate of carbon dioxide in the inlet stream. The absorbent liquid in the column may be maintained at a particular level. Because the absorbent is recirculated through the system, it does not have to accumulate at the bottom of the column. A controller may be utilized to sense the amount of absorbent at the bottom of the column and adjust or maintain the absorbent level at a desired level in the column.

[0415] In certain embodiments, CO 2 The absorption column operates under the following conditions: CO 2 Partial pressure: 13bar (1300kPa) Temperature: 28.1℃ Liquid phase viscosity: 110cP Vapor viscosity: 0.017cP CO in the absorbent 2 Diffusion rate: 500mm 2 / s Column diameter: 0.5m Column height: 12.4m Pressure drop: 0.012bar (1.2kPa) Cf (filling constant): 170 Total filling area: 108m 2 / m 3 Nominal filling diameter: 0.005m

[0416] CO and H 2 A gas stream (stream (3)) exits the top of the absorption column 2355. This stream may be used as synthesis gas.

[0417] CO from absorption column 2355 2 The enriched liquid phase is heated in heat exchanger 2356 (stream 5) before entering stripping column 2357 (stream 6). 2 has low solubility, and most of the CO 2is evaporated. The liquid phase flows to the bottom of stripping column 2357 (stream 8) where a portion of it is recycled back to column 2357 using reboiler 2358 (streams 9 / 10), while the remaining liquid flows back to absorption column 2355 (streams 11-16). In certain embodiments, about 4%-5% of the bottoms liquid at the bottom of the absorption column is recycled back to the column using, for example, a reboiler.

[0418] In certain embodiments, CO 2 The stripping column operates at a pressure of approximately 0.5 bar (50 kPa) to 5 bar (500 kPa) (e.g., about 1 bar (100 kPa)) and has an inlet CO 2 The enriched absorbent stream has a temperature of about 40°C to 60°C and the bottom of the column has a temperature of about 60°C to 80°C. Ethylene Refining

[0419] The embodiments described in this section relate to making ethylene. The embodiments described herein relate to methods and systems configured to receive a mixture containing ethylene and modify the mixture to produce purified ethylene. In some cases, the input is a gas mixture obtained from a carbon oxide electrolyzer, such as one of the carbon oxide electrolyzers described herein.

[0420] In some implementations, the ethylene purification system is configured to produce relatively pure ethylene without necessarily producing relatively pure streams of any other components produced by the electrolyzer, hi some implementations, the ethylene purification system is configured to produce relatively pure ethylene along with relatively pure streams of one or more other components, such as hydrogen, carbon monoxide, carbon dioxide, methane, ethanol, or any combination thereof.

[0421] In various embodiments, the ethylene purification system includes one or more components or subsystems for (a) absorbing and separating carbon dioxide, (b) separating ethylene from one or more other components by membrane filtration, (c) fractionation to separate ethylene and methane, (d) chemically converting methane to ethylene, and (e) any combination of (a)-(d). In some embodiments, an amine or ionic liquid is used to absorb the carbon dioxide. In some embodiments, the membrane filtration component is configured to separate carbon monoxide and hydrogen from the ethylene (optionally along with methane).

[0422] Ethylene produced as described herein may have a variety of applications, for example, it can be used to produce ethylene oxide (see, e.g., the discussion of Figures 10A, 11, and 14), and in some cases, reaction products of ethylene oxide, such as monoethylene glycol and polyethylene glycol.

[0423] In the particular embodiment described in this section, the input gas contains ethylene, and typically some methane and unreacted carbon dioxide. Other components that may be present include hydrogen, carbon monoxide, water, ethanol, and any combination thereof.

[0424] Various cryogenic distillation and membrane separation techniques for producing purified ethylene are presented in U.S. Provisional Patent Application No. 63 / 263,567, filed November 4, 2021, which is incorporated by reference in its entirety herein. Oxygen Generation

[0425] The carbon oxide electrolyzer anode may generate oxygen from water. The oxygen may be utilized in any of a variety of integration schemes for the electrolyzer. In some cases, the oxygen may be used in a combustion reaction with a fuel. In some cases, the oxygen may be compressed and stored for later use. In certain embodiments, the compressed oxygen is cooled and then passed through a throttle valve to liquefy the oxygen. Cooling may be accomplished using a Freon type cooler. In some cases, the oxygen stream is first cooled using a brine cooler (e.g., by cooling the oxygen using a brine cooler, e ... 2 For example, at 40 bar (4000 kPa) and -120°C, oxygen becomes a liquid. In some implementations, the oxygen stream is cooled to about -70°C or below. Heat produced by carbon oxide electrolyzers

[0426] During normal operation, the carbon oxide electrolyzer may generate heat. In some cases, about 25%-50% of the power supplied to the carbon oxide electrolyzer is converted to heat. Some or all of the generated heat may be used in one or more downstream or upstream processes. In some embodiments, the carbon dioxide electrolyzer generates a gas and / or liquid stream that includes thermal energy. In some cases, the gas and / or liquid stream has a temperature of about 25° C.-90° C. In certain implementations, the carbon oxide electrolyzer generates a cathode output gas stream that includes heat that may be supplied by the integrated system to one or more upstream or downstream units or subsystems. In some implementations, the carbon oxide electrolyzer generates an anode liquid output stream that includes heat that may be supplied by the integrated system to one or more upstream or downstream units or subsystems. In some cases, the carbon oxide electrolyzer includes dedicated heat transfer elements, such as jackets and / or conduits, through which a coolant circulates during operation. In some implementations, one or more bipolar plates of the electrolyzer are configured to circulate such a coolant therethrough. Heat transferred from the electrolyzer to the coolant may be supplied to other units or subsystems in the integrated system.

[0427] In some embodiments, the heat generated by the electrolyzer is used to preheat an inlet stream to a subsystem such as a boiler. In some embodiments, the heat generated by the electrolyzer is used in a thermal swing process such as a direct air process for capturing carbon dioxide, a carbon dioxide stripping process, and / or a carbon monoxide stripping process. In the integrated embodiments described herein, any upstream or downstream unit operation that can utilize the type of heat generated by the carbon oxide electrolyzer in the integrated embodiments may be configured to receive heat from the electrolyzer. Examples include dryers, separators, and reactors, including those for making polymers or bulk chemicals such as any of those disclosed herein. Thus, during normal operation, the system may deliver heat generated by the carbon oxide electrolyzer to one or more separation subsystems that utilize such heat to facilitate their own operation.

[0428] As described above, some integrated system embodiments utilize a direct air capture subsystem and a carbon oxide electrolyzer configured to deliver excess heat from the electrolyzer to the direct air capture subsystem. In a temperature swing implementation, the direct air capture unit requires a significant amount of thermal energy to capture and release a significant amount of carbon dioxide. As an example, the DAC unit may require at least about 1200 kWh (4.32 GJ) of thermal energy per ton of captured CO2. Furthermore, with a temperature swing, the DAC unit may desorb CO2 at an elevated temperature, which may be as low as about 70°C.

[0429] Generally, any output of the CO2 electrolyser can be used to provide heat to the DAC unit. Examples of such outputs include the anode water and gas output from the cathode side of the electrolyser. As an example, some CO2 electrolysers operate in a temperature range of about 20°C to about 110°C, and the anode water and / or gas product streams may leave the electrolyser at temperatures within this range.

[0430] In certain embodiments, the anode water leaving the electrolyzer is used to heat components of the DAC unit. In certain embodiments, the heat retained by the anode water can contribute up to about 40% of the thermal duty required by the DAC unit. Of course, the fractional contribution depends on various factors, including the operating temperature of the electrolyzer and the electrolysis energy efficiency.

[0431] In some embodiments, the gas stream leaving the electrolyzer may contribute up to about 5% of the heat required by the DAC unit, again depending on the operating temperature and electrolysis energy efficiency of the electrolyzer.

[0432] A temperature swing DAC unit typically includes an adsorbent packed bed that is maintained at a low or ambient temperature during operation when absorbing carbon dioxide and is raised to a higher temperature when desorbing carbon dioxide. During desorption, the packed bed may be heated using an electric heater, steam, or some other heating agent. In the DAC embodiments described herein, one or more heat exchangers may be utilized to provide heat to the packed bed. In some embodiments, at least one such heat exchanger receives heat from the electrolyzer and / or from the reactor for exothermic reactions. The positioning of such heat exchangers depends on various design considerations. Among other things, the DAC unit may have additional inlet and outlet pipes to accommodate streams generated by the electrolyzer and / or other reactors. However, the DAC unit itself (packed bed, blower, enclosure, etc.) may remain unmodified.

[0433] 24A shows an integrated system 2401 including a direct air capture unit 2405, a carbon dioxide electrolyzer 2403, and an anode purification unit 2407. In system 2401, the direct air capture unit 2405 receives air or another source of impure carbon dioxide 2409 and outputs two streams: a stream of purified air 2411 and a stream of purified carbon dioxide 2413. The system is configured to provide the purified stream of carbon dioxide 2413 to the cathode inlet of the carbon dioxide electrolyzer 2403.

[0434] The carbon dioxide electrolyzer 2403 is optionally configured to produce an output gas stream 2415 comprising one or more carbon-containing reduction products of carbon dioxide along with other components, such as unreacted carbon dioxide and impurities, in the inlet carbon dioxide stream 2413.

[0435] As shown elsewhere herein, the cathode side output gas stream (e.g., gas stream 2415) typically includes waste heat from the operation of an electrolyzer, such as carbon dioxide electrolyzer 2403. System 2401 is configured to deliver gas stream 2415, which may have an elevated temperature, for example, between about 70° C. and 200° C., to the inlet of direct air capture unit 2405. Unit 2405 is configured to extract heat from gas stream 2415 and use the extracted heat to facilitate purification of air stream 2409 to produce purified carbon dioxide stream 2413. As shown, the desorption process of the temperature swing of the direct air capture unit may be performed at an elevated temperature, and may reach such a temperature that may be achieved, at least in part, by using the waste heat of gas stream 2415. After providing some heat to direct air capture unit 2405, gas stream 2415 exits unit 2405 at a lower temperature and with a lower enthalpy than when the stream entered unit 2405. In some embodiments (not shown here), after exiting unit 2405, gas stream 2415 is purified by removing some or all of the unreacted carbon dioxide that may remain in the stream. In further embodiments, the carbon dioxide separated from gas stream 2415 may be recycled by providing it back to the cathode side of electrolyzer 2403, optionally by combining it with purified carbon dioxide stream 2413.

[0436] The system 2401 is configured to provide an anode water inlet stream 2419 to the anode side of a carbon dioxide electrolyzer 2403, which reduces water and outputs molecular oxygen (not shown), along with anode water 2417 containing unreacted water that is provided as input to the electrolyzer.

[0437] The anode water 2417 exiting the electrolytic cell 2403 contains some waste heat generated during operation of the electrolytic cell. The system 2401 is configured to deliver the anode water 2417 directly to an air capture unit 2405. Within the unit 2405, the heated anode water in stream 2417 may function similarly to a heated output gas stream 2415. That is, excess heat in the anode water stream 2417 may be extracted by the direct air capture unit 2405 to facilitate desorption of the carbon dioxide provided in the purified carbon dioxide stream 2413.

[0438] As shown, the anode water flowing through the direct air capture unit 2405 exits the unit 2405 via output anode water stream 2421. The anode water in stream 2421 is then provided to an anode water purification unit 2407 where the anode water is treated to remove impurities it may pick up as it passes through, for example, a CO electrolyzer. The anode water purification unit 2407 is configured to output a purified anode water stream 2423, which flows back to the inlet of the electrolyzer 2403 as purified anode water.

[0439] Note that some make-up anode water may be provided as shown in system 2401 via anode water make-up stream 2425. The make-up water may replace some anode water consumed by oxidation at the anode of carbon dioxide electrolyzer 2403. Additionally, in some implementations, a portion of the recycled anode water is continuously gradually discharged and purified, for example, by reverse osmosis, optionally performed by anode water purification unit 2407. Make-up anode water also replaces the gradually discharged anode water. Typically, the DAC unit does not consume any anode water or cathode product streams, although it may reduce the temperature of these streams.

[0440] Fischer-Tropsch (FT) reactions can occur in the temperature range of 150°C to 350°C. These reactions are highly exothermic due to the standard enthalpy of reaction of CO of -152 kJ / mol to -165 kJ / mol. However, the reaction temperature should be maintained as constant. This may be achieved by the application of hot water at the inlet of the Fischer-Tropsch reactor, which increases the excess heat of reaction and converts it into steam, which then leaves the reactor.

[0441] The generated steam from the FT process may be connected to a DAC unit where it transfers energy to the packed bed of the DAC unit to facilitate the desorption of carbon dioxide. In a heat transfer process, the steam from the FT process is converted to hot water.

[0442] When the heat generated by the FT reaction is consumed by the internal heat requirements of the FT reaction, there can be about 900 kWh to 1400 kWh of waste heat per ton of CO consumed for integration with the DAC unit. Thus, the FT waste heat encompasses about 75% to 100% of the thermal duty of the DAC unit in some embodiments.

[0443] Figure 24B shows an integrated system 2420 including a carbon dioxide electrolyzer 2403 (similar to the electrolyzer shown in Figure 24A) and a direct air capture unit 2426 configured to interact in a similar manner as system 2401 of Figure 24A. For example, system 2420 is configured to provide purified carbon dioxide stream 2442 generated by DAC unit 2426 to carbon dioxide electrolyzer 2403. Unit 2426 is also configured to receive air or other impure carbon dioxide via inlet stream 2443 and deliver purified air via stream 2445.

[0444] However, unlike system 2401, system 2420 of Figure 24B includes a Fischer-Tropsch synthesis unit 2428, and several additional modules used in support of the Fischer-Tropsch reaction. These additional units include a gas separation unit 2429 configured to receive an outlet gas stream 2430 from the carbon dioxide electrolyzer and separate the gas stream into a purified carbon monoxide stream 2431 and a purified carbon dioxide vapor 2432. In some embodiments, system 2420 is configured to deliver the purified carbon dioxide stream 2432 back to the carbon dioxide electrolyzer 2403 where it can be reduced.

[0445] System 2420 also includes a water electrolyzer 2427 configured to electrochemically reduce water from inlet water stream 2446 to produce hydrogen stream 2433. System 2420 is also configured to combine, e.g., via conduits and / or a mixing unit, hydrogen stream 2433 and carbon monoxide stream 2431 to produce syngas stream 2434.

[0446] In the integrated system 2420, the Fischer-Tropsch synthesis unit 2428 is configured to receive a syngas gas stream 2434 and react it via an exothermic FT reaction to produce various Fischer-Tropsch products 2444, such as those described elsewhere herein. To maintain the Fischer-Tropsch synthesis reaction at a suitable temperature, the unit 2428 is configured to receive hot water from a hot water inlet stream 2435. During the Fischer-Tropsch reaction, a water stream receives excess heat produced by the reaction and converts it to a saturated steam stream 2436.

[0447] In system 2420, the heat required by the DAC unit 2426 may be fully or substantially provided by the heat-containing streams from the Fischer-Tropsch synthesis unit 2428 and the carbon dioxide electrolyzer 2403. As described with respect to the system of FIG. 24A, the waste heat from operating the electrolyzer 2403 can be conveyed to the DAC unit via one or both of the gas stream 2415 exiting the cathode side of the electrolyzer 2403 and the anode water stream 2417 exiting the anode side of the electrolyzer 2403. In the DAC unit 2426, the heat from the gas stream 2415 is transferred to the unit via the heat exchanger 2437. And the heat from the anode water outlet stream 2417 is provided to the DAC unit 2426 via the heat exchanger 2438.

[0448] The anode water exiting the heat exchanger 2438 is provided to the anode water purification unit 2407 via the stream 2439, which serves the same purpose as the unit 2407 in the system 2401 of FIG. 24A. The purified anode water is recycled to the anode side of the electrolyzer 2403 via the anode water inlet 2419. The anode water makeup stream 2425 may be used in the same manner as in the system 2401. The gas stream 2415 from the electrolyzer 2403 exits the DAC heat exchanger 2426 as the gas stream 2430, and the gas stream is fed to the gas separation unit 2429.

[0449] The surplus heat generated by the Fischer-Tropsch synthesis unit 2428 may be retained via the saturated vapor stream 2436 and delivered to the heat exchanger 2440 within the DAC unit 2426. The heat from the saturated vapor stream 2436 may be delivered to the desorption component of the DAC unit 2426 to facilitate the release of carbon dioxide in a temperature swing operation. In the illustrated embodiment, the heat exchanger 2440 is configured to convert the saturated vapor of the stream 2436 into hot water, and the hot water is then delivered to return to the Fischer-Tropsch synthesis unit 2428 via the stream 2435.

[0450] As shown, the DAC unit may be heated using one or more heat exchangers, such as conventional heat exchangers. Each of heat exchangers 2437, 2438, and 2440 has one or more pipes leading to and from the DAC unit. However, the DAC unit itself, including its packed bed, blower, enclosed space, etc., otherwise remains the same. Note that heat exchanger 2440 may be sized and controlled in a manner to provide hot water in its outlet stream. The pressure and flow rate of the incoming saturated steam stream 2436 are controlled parameters. In certain embodiments, a flash tank is provided downstream of heat exchanger 2440 where condensed water is collected and pumped back to the FT unit.

[0451] Optionally, heat generated during operation of the water electrolyzer 2427 is provided to the DAC unit 2426 to drive the temperature swing process to produce purified carbon dioxide 2442.

[0452] Certain embodiments relate to an integrated system including a methanol synthesis reactor, a DAC unit, and a carbon dioxide electrolyzer. In some methanol synthesis reactors, CO produced by the carbon dioxide electrolyzer reacts with hydrogen in a packed bed reactor at elevated pressure and temperature to form methanol. Reaction -CO+2H2-->CH3OH Reaction enthalpy ΔH=-90.8kJ mol-1

[0453] The reaction may occur at temperatures above about 200°C, which is exothermic. The methanol reactor temperature may be maintained as constant and not exceed 250°C. This is accomplished by applying hot water at the inlet of the reactor, which increases the excess heat of reaction and converts it to steam, which leaves the reactor. Depending on the heat transfer efficiency, the waste heat from the methanol reactor, retained by the steam, may contribute about 35%-50% of the heat duty of the DAC unit.

[0454] Figure 24C shows an integrated methanol production system 2451 similar to integrated system 2420 of Figure 24B. However, rather than using a Fischer-Tropsch reactor, system 2451 utilizes a methanol synthesis reactor 2453. In Figure 24C, components with like reference numbers and connecting lines serve the same or similar purpose as corresponding components in Figure 24B.

[0455] As shown, methanol production system 2451 includes a carbon dioxide electrolyzer 2403, a DAC unit 2426, a water electrolyzer 2427, a gas separation unit 2429, and an anode water purification unit 2407 arranged and configured similarly to the corresponding components in Fischer-Tropsch synthesis system 2420 of Figure 24B. Similarly, these various units have inlet and outlet streams corresponding to those of system 2420 of Figure 24B.

[0456] Methanol synthesis unit 2453 is configured to receive hot water via input stream 2457, which maintains the temperature of the methanol synthesis reaction at the temperature of the hot water. Heat generated during the exothermic methanol synthesis reaction is transferred to the hot water, which is converted to saturated steam. Unit 2453 is configured to output saturated steam at an elevated temperature via stream 2459. System 2451 is configured to feed stream 2459 to a heat exchanger 2461 in DAC unit 2426, where excess heat from the saturated steam is transferred to unit 2426 to drive the carbon dioxide purification process.

[0457] In some cases, the only practical difference between the Fischer-Tropsch and methanol integrated systems 2420 and 2451 is in the chemical reactions and associated reaction enthalpies. For example, the steam in streams 2436 and 2459 may be at the same pressure and temperature in both cases. However, the steam flow in the methanol case is lower than in the Fischer-Tropsch case due to the lower reaction enthalpy.

[0458] In scenarios where hydrogen is required downstream of the CO2 electrolyser (such as for the production of syngas, fuels, methanol, acetic acid, acetone, etc.), the unreacted water leaving the H2O electrolyser at elevated temperatures may be used to heat the CO2 desorption packed bed in a temperature swing DAC unit.

[0459] After transferring some of its internal heat to the packed bed, oxygen may be recovered from the water, which may be recycled back to the HO electrolyzer. In some implementations, oxygen is recovered in the flash tank in the vapor phase, while water leaves the flash tank in the liquid phase. In some embodiments, unreacted water may contribute up to about 70% of the thermal duty of the DAC unit, depending on the energy efficiency, operating temperature, and excess water at the inlet of the electrolyzer.

[0460] Figure 24D shows a system 2465 that includes a carbon dioxide electrolyser 2403, a water electrolyser 2469, and a DAC unit 2467. Both electrolyzers generate waste heat that can be used by unit 2467 to drive carbon dioxide capture and purification.

[0461] The cathode side of the carbon dioxide electrolyzer 2403 is configured to receive purified carbon dioxide produced by the DAC unit 2467. The anode side of the carbon dioxide electrolyzer 2403 is configured to receive an anode water stream 2419. During operation, the cathode in the electrolyzer 2403 produces a gas stream 2415 containing one or more carbon-containing reduction products of carbon dioxide, and the anode in the electrolyzer 2403 produces oxygen in the exit anode water 2417.

[0462] Water electrolyzer 2469 is configured to receive water stream 2466 and provide water from that stream to both the anode and cathode. During operation of electrolyzer 2469, the anode produces molecular oxygen, which is output in stream 2468, along with unreacted water, while the cathode produces molecular hydrogen, which is output in stream 2470.

[0463] DAC unit 2467 is configured to receive air 2476 or another source of impure carbon dioxide and output purified air 2478 and purified carbon dioxide in stream 2480. DAC unit 2467 receives heat from at least three sources: gas stream 2415 via heat exchanger 2477, anode water stream 2417 via heat exchanger 2479, and oxygen / water stream 2468 via heat exchanger 2473.

[0464] After transferring a portion of its heat content to DAC unit 2467, oxygen / water stream 2468 exits unit 2467 as stream 2472. System 2465 includes an oxygen separation unit 2475 configured to receive stream 2472 and produce purified molecular oxygen 2474. During operation, oxygen separation unit 2475 also produces a water stream, which may be cooled by heat exchanger 2491 and recycled as input to water electrolyzer 2769 in stream 2466.

[0465] Gas stream 2415 enters DAC unit 2467 and, after transferring a portion of its heat, exits as gas stream 2484, which includes carbon dioxide and carbon monoxide. System 2465 includes a gas separation system 2471 configured to receive gas stream 2484 and produce a purified carbon dioxide stream 2486 and a purified carbon monoxide stream 2488. System 2465 is configured to recycle carbon dioxide stream 2486 from DAC unit 2467 back to carbon dioxide electrolyzer 2403 along with carbon dioxide stream 2480. System 2465 is configured to combine carbon monoxide stream 2488 with hydrogen stream 2470 to produce syngas 2490 stream.

[0466] Additionally, system 2465 includes an anode water purification unit 2407 configured to receive the anode water stream 2481 exiting heat exchanger 2479 and purify the anode water before returning it to the carbon dioxide electrolyzer 2403. Controller embodiment

[0467] In embodiments utilizing a controller or other logic to control the operation of one or more reactors, pumps, separators, and / or other components of the system, the controller or logic may utilize program instructions, such as executable instructions on a computer-readable medium. The instructions may be executed by a computer-executable component, such as one integrated with a communication system. The computer-readable medium may be stored on any suitable computer-readable medium, such as RAM, ROM, flash memory, EEPROM, optical device (CD or DVD), hard drive, floppy drive, or any suitable device. The computer-executable component is optionally a processor, although the instructions may alternatively or additionally be executed by any suitable dedicated hardware device.

[0468] Although omitted for brevity, system and / or method embodiments may include any combination and permutation of the various system components and various method processes, and one or more instances of the methods and / or processes described herein may be performed asynchronously (e.g., sequentially), simultaneously (e.g., in parallel), or in any other suitable order by and / or using one or more instances of the systems, elements, and / or entities described herein.

[0469] The figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to the disclosed embodiments, example configurations, and variations thereof. In this regard, each block in the flowcharts or block diagrams may represent a module, segment, step, or part of code, which includes one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions described in the blocks may occur out of the order described in the figures. For example, two blocks shown in succession may in fact be executed substantially simultaneously, or the blocks may be executed in the reverse order, depending on the functionality involved. It should also be noted that each block of the block diagrams and / or flowchart diagrams, and combinations of blocks in the block diagrams and / or flowchart diagrams, may be implemented by a dedicated hardware-based system that executes the specified functions or operations, or a combination of dedicated hardware and computer instructions.

[0470] Those skilled in the art will recognize from the foregoing detailed description and from the figures and claims that follow, that modifications and variations can be made to the disclosed embodiments of the present disclosure without departing from the scope of the disclosure, which is defined in the following claims.

Claims

1. (a) a carbon dioxide reduction electrolyzer having a membrane electrode assembly, the membrane electrode assembly having one or more ion-conducting polymer layers and a cathode catalyst for promoting the chemical reduction of carbon dioxide to carbon-containing compounds; (b) one or more reactors configured to receive the carbon-containing compounds or derivatives of the carbon-containing compounds produced by the carbon dioxide reduction electrolyzer and produce one or more product chemicals; and (c) a heat-receiving unit configured to receive excess heat produced by the carbon dioxide reduction electrolyzer and facilitate production of the one or more product chemicals. A system comprising:

2. 10. The system of claim 1, wherein the heat-receiving unit is further configured to provide excess heat to the one or more reactors configured to receive the carbon-containing compounds or the derivatives of the carbon-containing compounds produced by the carbon dioxide reduction electrolyzer and produce the one or more product chemicals.

3. 10. The system of claim 1, wherein the heat-receiving unit comprises a heat exchanger configured to receive the excess heat produced by the carbon dioxide reduction electrolyzer.

4. 10. The system of claim 1, wherein the heat-receiving unit comprises a reboiler configured to receive the excess heat produced by the carbon dioxide reduction electrolyzer.

5. 10. The system of claim 1, wherein the one or more reactors configured to receive the carbon-containing compound or the derivative of the carbon-containing compound produced by the carbon dioxide reduction electrolyzer comprise a Fischer-Tropsch reactor.

6. The system of claim 5 , wherein the heat-receiving unit is a reformer configured to react gaseous hydrocarbons with water.

7. The system of claim 5 , wherein the Fischer-Tropsch reactor is configured to produce naphtha.

8. 10. The system of claim 1, wherein the carbon-containing compound is CO and the heat-receiving unit is a CO purification unit.

9. 10. The system of claim 8, wherein the CO purification unit utilizes an adsorbent material.

10. (a) reducing carbon dioxide to carbon-containing compounds in a carbon dioxide reduction electrolyzer having a membrane electrode assembly having one or more ion-conducting polymer layers and a cathode catalyst for facilitating the chemical reduction of carbon dioxide to the carbon-containing compounds; (b) reacting the carbon-containing compound or a derivative of the carbon-containing compound produced by the carbon dioxide reduction electrolyzer in one or more reactions to produce one or more product chemicals; and (c) transferring excess heat produced by the carbon dioxide reduction electrolyzer to the one or more reactions to promote the production of the one or more product chemicals.

1. A method for producing a product chemical comprising:

11. The method for producing a product chemical of claim 10, wherein the one or more reactions are endothermic reactions.

12. 11. The method of claim 10, wherein (c) comprises providing the excess heat to a heat exchanger configured to receive the excess heat produced by the carbon dioxide reduction electrolyzer.

13. 11. The method of claim 10, wherein the one or more reactions comprise a Fischer-Tropsch reaction.

14. 14. The method of claim 13, wherein (c) comprises providing the excess heat to a reformer that reacts gaseous hydrocarbons with water.

15. 11. The method for producing a product chemical of claim 10, wherein the carbon-containing compound is CO, and (c) comprises providing the excess heat to a CO purification unit.

16. 16. The method for producing a product chemical as set forth in claim 15, wherein the CO purification unit utilizes an adsorbent material.

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